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BarneyL
Joined: 15 Apr 2017 Posts: 18 Location: Poland
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Posted: Sun May 26, 2019 7:12 pm Post subject: WTB: 300mm manual lens for astrophotography |
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BarneyL wrote:
Hello there,
This is both a WTB type of ad and a general inquiry about 300mm lenses. I'd like to use one for astro (Andromeda galaxy, that kind of stuff). I would prefer to not make my wallet cry in the process, therefore I'm looking into manual focus/vintage range.
What I'm looking for is:
- max aperture F/4 or faster (will consider F/5.6 one if it's really good wide open)
- usable on current DSLRs, with simple adapter or a Leitax mod (so basically Nikon F, Leica R, Contax/Yashica, Pentax K, M42 and Olympus OM mounts)
- decent CA control and resolving capability
Don't care about minimum focus distance or size/weight (although I'd like it to have max 77mm filter thread).
Will appreciate any suggestions... and offers.
Best regards |
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visualopsins
Joined: 05 Mar 2009 Posts: 10463 Location: California
Expire: 2021-06-22
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Posted: Sun May 26, 2019 9:46 pm Post subject: |
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visualopsins wrote:
Already have tracking mount? _________________ ☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮ like attracts like! ☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮
Cameras: Sony A7Rii, Spotmatics II, F, and ESII, Nikon P4
M42 Asahi Optical Co., Lenses:
Takumar 1:4 f=35mm, 1:2 f=58mm (Sonnar), 1:2.4 f=58mm (Heliar), 1:2.2 f=55mm (Gaussian), 1:2.8 f=105mm (Model I), 1:2.8/105 (Model II), 1:5.6/200
Tele-Takumar 1:5.6/200, 1:6.3/300
Macro-Takumar 1:4/50
Auto-Takumar 1:2.3 f=35, 1:1.8 f=55mm, 1:2.2 f=55mm
Super-TAKUMAR 1:3.5/28 (fat), 1:2/35 (Fat), 1:1.4/50 (8-element),
Super-Multi-Coated Fisheye-TAKUMAR 1:4/17
Super-Multi-Coated TAKUMAR 1:4.5/20, 1:3.5/24, 1:3.5/28, 1:2/35, 1:3.5/35, 1:1.8/85, 1:1.9/85 1:2.8/105, 1:3.5/135, 1:2.5/135 (II), 1:4/150, 1:4/200, 1:4/300, 1:4.5/500
Super-Multi-Coated Macro-TAKUMAR 1:4/50, 1:4/100
Super-Multi-Coated Bellows-TAKUMAR 1:4/100
SMC TAKUMAR 1:1.4/50, 1:1.8/55
Other lenses:
Carl Zeiss Jena Flektogon 2.4/35
SMC PENTAX ZOOM 1:3.5 35~105mm, SMC PENTAX ZOOM 1:4 45~125mm
Nikon Micro-NIKKOR-P-C Auto 1:3.5 f=55mm, NIKKOR-P Auto 105mm f/2.5 Pre-AI (Sonnar), Micro-NIKKOR 105mm 1:4 AI, NIKKOR AI-S 35-135mm f/3,5-4,5
Tamron SP 17mm f/3.5 (51B), Tamron SP 17mm f/3.5 (51BB), SP 500mm f/8 (55BB), SP 70-210mm f/3.5 (19AH)
Vivitar 100mm 1:2.8 MC 1:1 Macro Telephoto
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cooltouch
Joined: 15 Jan 2009 Posts: 9097 Location: Houston, Texas
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Posted: Sun May 26, 2019 11:14 pm Post subject: |
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cooltouch wrote:
Tracking mounts of the barndoor variety are easy enough to build. Just google the term for DIY info.
As for a good 300mm, other than hoping your wallet doesn't cry, you don't mention a specific budget, so I'll mention a few of my favorites, in descending order of cost.
Canon 300mm f/2.8 L (or the Nikon ED equivalent)
Tamron 300mm f/2.8 LDIF
Nikon 300mm f/4.5 ED
Tokina 100-300mm f/4 SD
Now, just because I include that Tokina zoom, don't reject it from consideration out of hand. I own a copy and it is definitely the sharpest short tele to 300mm zoom I own. It is an excellent lens.
You mention Andromeda specifically, and I'm assuming you're going to attempt photographing this galaxy. It is a nice photo subject. I have photographed Andromeda with a film camera. I was shooting slides at ISO 100. My camera was mounted to a Meade 10" mirror, that had a focal length of 2540mm, which was necessary to get even close to filling the frame. It also took 30 minutes of tracking the galaxy for sufficient exposure. So, my opinion? 300mm is way too tiny of a focal length for such a distant object. It's even too small for the Orion Nebula, which is a good deal more prominent. Heck, 300mm is about as small as you want to go for shooting photos of the moon! So for deep space photography, I'd say that you're gonna need at least an 8" mirror with a good clock drive to make decent recordings of many of the deep space objects that are desirable photo subjects. Unfortunately, a good 8" with a decent clock drive and a paddle, even used, is gonna cause your wallet to cry quite a lot, I'd say. _________________ Michael
My Gear List: http://michaelmcbroom.com/photo/gear.html
My Gallery: http://michaelmcbroom.com/gallery3/index.php/
My Flickr Page: https://www.flickr.com/photos/11308754@N08/albums
My Music: https://soundcloud.com/michaelmcbroom/albums
My Blog: http://michaelmcbroom.com/blogistan/ |
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visualopsins
Joined: 05 Mar 2009 Posts: 10463 Location: California
Expire: 2021-06-22
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Posted: Mon May 27, 2019 2:38 am Post subject: |
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visualopsins wrote:
A fast 50mm lens makes nice night sky images without need for tracking mount.
Rent time on really nice Internet controlled equipment, https://www.itelescope.net/ _________________ ☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮ like attracts like! ☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮
Cameras: Sony A7Rii, Spotmatics II, F, and ESII, Nikon P4
M42 Asahi Optical Co., Lenses:
Takumar 1:4 f=35mm, 1:2 f=58mm (Sonnar), 1:2.4 f=58mm (Heliar), 1:2.2 f=55mm (Gaussian), 1:2.8 f=105mm (Model I), 1:2.8/105 (Model II), 1:5.6/200
Tele-Takumar 1:5.6/200, 1:6.3/300
Macro-Takumar 1:4/50
Auto-Takumar 1:2.3 f=35, 1:1.8 f=55mm, 1:2.2 f=55mm
Super-TAKUMAR 1:3.5/28 (fat), 1:2/35 (Fat), 1:1.4/50 (8-element),
Super-Multi-Coated Fisheye-TAKUMAR 1:4/17
Super-Multi-Coated TAKUMAR 1:4.5/20, 1:3.5/24, 1:3.5/28, 1:2/35, 1:3.5/35, 1:1.8/85, 1:1.9/85 1:2.8/105, 1:3.5/135, 1:2.5/135 (II), 1:4/150, 1:4/200, 1:4/300, 1:4.5/500
Super-Multi-Coated Macro-TAKUMAR 1:4/50, 1:4/100
Super-Multi-Coated Bellows-TAKUMAR 1:4/100
SMC TAKUMAR 1:1.4/50, 1:1.8/55
Other lenses:
Carl Zeiss Jena Flektogon 2.4/35
SMC PENTAX ZOOM 1:3.5 35~105mm, SMC PENTAX ZOOM 1:4 45~125mm
Nikon Micro-NIKKOR-P-C Auto 1:3.5 f=55mm, NIKKOR-P Auto 105mm f/2.5 Pre-AI (Sonnar), Micro-NIKKOR 105mm 1:4 AI, NIKKOR AI-S 35-135mm f/3,5-4,5
Tamron SP 17mm f/3.5 (51B), Tamron SP 17mm f/3.5 (51BB), SP 500mm f/8 (55BB), SP 70-210mm f/3.5 (19AH)
Vivitar 100mm 1:2.8 MC 1:1 Macro Telephoto
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BarneyL
Joined: 15 Apr 2017 Posts: 18 Location: Poland
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Posted: Mon May 27, 2019 9:09 am Post subject: |
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BarneyL wrote:
Thank you everyone for replies.
@visualopsins - I have some sort of a tracking device built into the camera (Pentax K-1). It's called Astrotracer. It uses sensor stabilization mechanism to move the sensor to track the stars. It does have some limitations compared to the dedicated tracking mounts of course, but so far I'm pretty happy using it to shoot Milky Way and such.
@cooltouch - yes, I guess "make a wallet cry" isn't too specific of a description. It really depends. There are some vintage glass that's both good and accordingly priced; there are also some good, but with collector-inflated price. I have no problem paying for quality, but I'd prefer not to spend much on rarity tax.
Since you said that 300mm isn't really enough for the imagery I'd like to try getting, I have some second thoughts. However, I have seen some pretty nice images of deep sky objects made with 300mm (or even with slow aperture 18-135 aps-c kit lens). Modern high resolution sensors give quite a lot of room for cropping.
https://www.dpreview.com/forums/post/54617583
http://www.ricoh-imaging.co.jp/english/photo-life/astro/
From those lenses you mentioned, Canon EF is of course out of question for me, but the others I could work with. Nikon (assuming it's manual focus lens) would require some DYI to work, but I'm up to it if it's worth it. Tamron and Tokina had K mount options, so these are quite appealing, and from what I've seen, reasonably priced. I will certainly consider them.
Just out of curiosity - what do you people think about Zeiss Contax Tele-Tessar 300 F4? It seems pretty cheap for a Zeiss glass. |
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stupidblogger
Joined: 11 Jun 2019 Posts: 1
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Posted: Tue Jun 11, 2019 9:48 am Post subject: WTB: 300mm manual lens for astrophotography |
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stupidblogger wrote:
Nikon's full frame cameras like the D750 are a top choice for astrophotography. The Tamron 15-30mm f/2.8 is sharper and more affordable than Nikon's already excellent 14-24mm f/2.8 and Sigma's 35mm and 50mm Art lenses set the standard for fast primes in terms of sharpness and value.
I appreciate reading some replies. i have got many knowledge and ideas about apple macbook.
Thank you for sharing.
if you want to gain more knowledge related technology so you can read on https://www.stupidblogger.com/ & get more interesting facts and news. |
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visualopsins
Joined: 05 Mar 2009 Posts: 10463 Location: California
Expire: 2021-06-22
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Posted: Tue Jun 11, 2019 10:20 am Post subject: |
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visualopsins wrote:
BarneyL wrote: |
Thank you everyone for replies.
@visualopsins - I have some sort of a tracking device built into the camera (Pentax K-1). It's called Astrotracer. It uses sensor stabilization mechanism to move the sensor to track the stars. It does have some limitations compared to the dedicated tracking mounts of course, but so far I'm pretty happy using it to shoot Milky Way and such.
@cooltouch - yes, I guess "make a wallet cry" isn't too specific of a description. It really depends. There are some vintage glass that's both good and accordingly priced; there are also some good, but with collector-inflated price. I have no problem paying for quality, but I'd prefer not to spend much on rarity tax.
Since you said that 300mm isn't really enough for the imagery I'd like to try getting, I have some second thoughts. However, I have seen some pretty nice images of deep sky objects made with 300mm (or even with slow aperture 18-135 aps-c kit lens). Modern high resolution sensors give quite a lot of room for cropping.
https://www.dpreview.com/forums/post/54617583
http://www.ricoh-imaging.co.jp/english/photo-life/astro/
From those lenses you mentioned, Canon EF is of course out of question for me, but the others I could work with. Nikon (assuming it's manual focus lens) would require some DYI to work, but I'm up to it if it's worth it. Tamron and Tokina had K mount options, so these are quite appealing, and from what I've seen, reasonably priced. I will certainly consider them.
Just out of curiosity - what do you people think about Zeiss Contax Tele-Tessar 300 F4? It seems pretty cheap for a Zeiss glass. |
Astrotracer works with lenses 135mm and less.
Following those links I didn't see any deep sky objects photographed using 300mm lens. _________________ ☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮ like attracts like! ☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮
Cameras: Sony A7Rii, Spotmatics II, F, and ESII, Nikon P4
M42 Asahi Optical Co., Lenses:
Takumar 1:4 f=35mm, 1:2 f=58mm (Sonnar), 1:2.4 f=58mm (Heliar), 1:2.2 f=55mm (Gaussian), 1:2.8 f=105mm (Model I), 1:2.8/105 (Model II), 1:5.6/200
Tele-Takumar 1:5.6/200, 1:6.3/300
Macro-Takumar 1:4/50
Auto-Takumar 1:2.3 f=35, 1:1.8 f=55mm, 1:2.2 f=55mm
Super-TAKUMAR 1:3.5/28 (fat), 1:2/35 (Fat), 1:1.4/50 (8-element),
Super-Multi-Coated Fisheye-TAKUMAR 1:4/17
Super-Multi-Coated TAKUMAR 1:4.5/20, 1:3.5/24, 1:3.5/28, 1:2/35, 1:3.5/35, 1:1.8/85, 1:1.9/85 1:2.8/105, 1:3.5/135, 1:2.5/135 (II), 1:4/150, 1:4/200, 1:4/300, 1:4.5/500
Super-Multi-Coated Macro-TAKUMAR 1:4/50, 1:4/100
Super-Multi-Coated Bellows-TAKUMAR 1:4/100
SMC TAKUMAR 1:1.4/50, 1:1.8/55
Other lenses:
Carl Zeiss Jena Flektogon 2.4/35
SMC PENTAX ZOOM 1:3.5 35~105mm, SMC PENTAX ZOOM 1:4 45~125mm
Nikon Micro-NIKKOR-P-C Auto 1:3.5 f=55mm, NIKKOR-P Auto 105mm f/2.5 Pre-AI (Sonnar), Micro-NIKKOR 105mm 1:4 AI, NIKKOR AI-S 35-135mm f/3,5-4,5
Tamron SP 17mm f/3.5 (51B), Tamron SP 17mm f/3.5 (51BB), SP 500mm f/8 (55BB), SP 70-210mm f/3.5 (19AH)
Vivitar 100mm 1:2.8 MC 1:1 Macro Telephoto
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BarneyL
Joined: 15 Apr 2017 Posts: 18 Location: Poland
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Posted: Sun Jun 16, 2019 9:16 am Post subject: |
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BarneyL wrote:
First link shows images of Andromeda and the Pleiades shot using Sigma 300mm/2.8.
Also, Astrotracer does work with lenses longer than 135mm. It's just not as effective. |
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visualopsins
Joined: 05 Mar 2009 Posts: 10463 Location: California
Expire: 2021-06-22
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Posted: Sun Jun 16, 2019 9:27 am Post subject: |
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visualopsins wrote:
Deep sky objects can't readily be seen with naked eye as can Andromeda and Pleiades.
Astrotracer sales literature specifically says up to 135mm. _________________ ☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮ like attracts like! ☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮
Cameras: Sony A7Rii, Spotmatics II, F, and ESII, Nikon P4
M42 Asahi Optical Co., Lenses:
Takumar 1:4 f=35mm, 1:2 f=58mm (Sonnar), 1:2.4 f=58mm (Heliar), 1:2.2 f=55mm (Gaussian), 1:2.8 f=105mm (Model I), 1:2.8/105 (Model II), 1:5.6/200
Tele-Takumar 1:5.6/200, 1:6.3/300
Macro-Takumar 1:4/50
Auto-Takumar 1:2.3 f=35, 1:1.8 f=55mm, 1:2.2 f=55mm
Super-TAKUMAR 1:3.5/28 (fat), 1:2/35 (Fat), 1:1.4/50 (8-element),
Super-Multi-Coated Fisheye-TAKUMAR 1:4/17
Super-Multi-Coated TAKUMAR 1:4.5/20, 1:3.5/24, 1:3.5/28, 1:2/35, 1:3.5/35, 1:1.8/85, 1:1.9/85 1:2.8/105, 1:3.5/135, 1:2.5/135 (II), 1:4/150, 1:4/200, 1:4/300, 1:4.5/500
Super-Multi-Coated Macro-TAKUMAR 1:4/50, 1:4/100
Super-Multi-Coated Bellows-TAKUMAR 1:4/100
SMC TAKUMAR 1:1.4/50, 1:1.8/55
Other lenses:
Carl Zeiss Jena Flektogon 2.4/35
SMC PENTAX ZOOM 1:3.5 35~105mm, SMC PENTAX ZOOM 1:4 45~125mm
Nikon Micro-NIKKOR-P-C Auto 1:3.5 f=55mm, NIKKOR-P Auto 105mm f/2.5 Pre-AI (Sonnar), Micro-NIKKOR 105mm 1:4 AI, NIKKOR AI-S 35-135mm f/3,5-4,5
Tamron SP 17mm f/3.5 (51B), Tamron SP 17mm f/3.5 (51BB), SP 500mm f/8 (55BB), SP 70-210mm f/3.5 (19AH)
Vivitar 100mm 1:2.8 MC 1:1 Macro Telephoto
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cooltouch
Joined: 15 Jan 2009 Posts: 9097 Location: Houston, Texas
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Posted: Sun Jun 16, 2019 1:32 pm Post subject: |
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cooltouch wrote:
BarneyL wrote: |
@cooltouch - yes, I guess "make a wallet cry" isn't too specific of a description. It really depends. There are some vintage glass that's both good and accordingly priced; there are also some good, but with collector-inflated price. I have no problem paying for quality, but I'd prefer not to spend much on rarity tax.
Since you said that 300mm isn't really enough for the imagery I'd like to try getting, I have some second thoughts. However, I have seen some pretty nice images of deep sky objects made with 300mm (or even with slow aperture 18-135 aps-c kit lens). Modern high resolution sensors give quite a lot of room for cropping.
https://www.dpreview.com/forums/post/54617583
http://www.ricoh-imaging.co.jp/english/photo-life/astro/
From those lenses you mentioned, Canon EF is of course out of question for me, but the others I could work with. Nikon (assuming it's manual focus lens) would require some DYI to work, but I'm up to it if it's worth it. Tamron and Tokina had K mount options, so these are quite appealing, and from what I've seen, reasonably priced. I will certainly consider them.
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Well, once again digital is proving just how different the world of photography has become. The link you provide for the Andromeda galaxy, which was shot with a Sigma 300mm f/2.8 lens, looks almost the same as the image I shot using my old Meade 2540mm 10" f/10 LX3, a Nikon F2 and Fujichrome 100 film. I had to track that object, using an off-axis guider and a paddle for 30 minutes to get my shot. But no enlargement was required
I'm curious how much the image taken with that Sigma 300mm had to be cropped by. It had to have been by a sizable amount. That cropped image is only about 1600-some pixels (1.8 MB), so I'm figuring at least a 25% crop. Also, this guy has recorded the shutter speed for that image as 1/10000 second. Can somebody explain to me how this is even possible with a deep sky object such as this? And at that high of a shutter speed, what does the guy need a tracker for? Something doesn't make sense. Looking at the Astrotrace home page, the images shown there have much longer exposure times.
Too bad it works only for Pentax digitals. _________________ Michael
My Gear List: http://michaelmcbroom.com/photo/gear.html
My Gallery: http://michaelmcbroom.com/gallery3/index.php/
My Flickr Page: https://www.flickr.com/photos/11308754@N08/albums
My Music: https://soundcloud.com/michaelmcbroom/albums
My Blog: http://michaelmcbroom.com/blogistan/ |
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BarneyL
Joined: 15 Apr 2017 Posts: 18 Location: Poland
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Posted: Tue Jun 18, 2019 7:55 pm Post subject: |
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BarneyL wrote:
cooltouch wrote: |
Also, this guy has recorded the shutter speed for that image as 1/10000 second. Can somebody explain to me how this is even possible with a deep sky object such as this? And at that high of a shutter speed, what does the guy need a tracker for? Something doesn't make sense. Looking at the Astrotrace home page, the images shown there have much longer exposure times.
Too bad it works only for Pentax digitals. |
I think something went messy when he uploaded the pictures to DPR. Anyway, he wrote that Andromeda picture consists of stacked 15 exposures, 300 seconds total (so on average 20s for each). |
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cooltouch
Joined: 15 Jan 2009 Posts: 9097 Location: Houston, Texas
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Posted: Tue Jun 18, 2019 8:08 pm Post subject: |
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cooltouch wrote:
Ah, ok. Stacked 20 second photos and you don't need any sort of tracker. At 20 seconds and 300mm, points are still points. _________________ Michael
My Gear List: http://michaelmcbroom.com/photo/gear.html
My Gallery: http://michaelmcbroom.com/gallery3/index.php/
My Flickr Page: https://www.flickr.com/photos/11308754@N08/albums
My Music: https://soundcloud.com/michaelmcbroom/albums
My Blog: http://michaelmcbroom.com/blogistan/ |
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visualopsins
Joined: 05 Mar 2009 Posts: 10463 Location: California
Expire: 2021-06-22
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Posted: Tue Jun 18, 2019 8:19 pm Post subject: |
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visualopsins wrote:
M42 Super- or Super-Multi-Coated TAKUMAR 300/4
I don't understand why AstroTracker and stacking is necessary given a tracking mount. Why not just use the tracking mount and long exposures?
Another option is a 2X teleconverter used with a reasonably fast 135mm... _________________ ☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮ like attracts like! ☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮
Cameras: Sony A7Rii, Spotmatics II, F, and ESII, Nikon P4
M42 Asahi Optical Co., Lenses:
Takumar 1:4 f=35mm, 1:2 f=58mm (Sonnar), 1:2.4 f=58mm (Heliar), 1:2.2 f=55mm (Gaussian), 1:2.8 f=105mm (Model I), 1:2.8/105 (Model II), 1:5.6/200
Tele-Takumar 1:5.6/200, 1:6.3/300
Macro-Takumar 1:4/50
Auto-Takumar 1:2.3 f=35, 1:1.8 f=55mm, 1:2.2 f=55mm
Super-TAKUMAR 1:3.5/28 (fat), 1:2/35 (Fat), 1:1.4/50 (8-element),
Super-Multi-Coated Fisheye-TAKUMAR 1:4/17
Super-Multi-Coated TAKUMAR 1:4.5/20, 1:3.5/24, 1:3.5/28, 1:2/35, 1:3.5/35, 1:1.8/85, 1:1.9/85 1:2.8/105, 1:3.5/135, 1:2.5/135 (II), 1:4/150, 1:4/200, 1:4/300, 1:4.5/500
Super-Multi-Coated Macro-TAKUMAR 1:4/50, 1:4/100
Super-Multi-Coated Bellows-TAKUMAR 1:4/100
SMC TAKUMAR 1:1.4/50, 1:1.8/55
Other lenses:
Carl Zeiss Jena Flektogon 2.4/35
SMC PENTAX ZOOM 1:3.5 35~105mm, SMC PENTAX ZOOM 1:4 45~125mm
Nikon Micro-NIKKOR-P-C Auto 1:3.5 f=55mm, NIKKOR-P Auto 105mm f/2.5 Pre-AI (Sonnar), Micro-NIKKOR 105mm 1:4 AI, NIKKOR AI-S 35-135mm f/3,5-4,5
Tamron SP 17mm f/3.5 (51B), Tamron SP 17mm f/3.5 (51BB), SP 500mm f/8 (55BB), SP 70-210mm f/3.5 (19AH)
Vivitar 100mm 1:2.8 MC 1:1 Macro Telephoto
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cooltouch
Joined: 15 Jan 2009 Posts: 9097 Location: Houston, Texas
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Posted: Wed Jun 19, 2019 1:13 am Post subject: |
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cooltouch wrote:
Have you ever had to track a celestial object for a minimum of a half hour to have enough exposure time for an astrophotograph? I have. And you don't even get to look at the object you're taking a picture of. Or at least you didn't when I was doing it back in the 90s. Maybe they've improved things since then. But I had to use an off-axis guider and the way it worked was you tracked a single star somewhere out of the field of view, keeping your crosshairs centered on that one dinky star for a half hour. After you've done a lot of that, stacking seems like a God-send.
Prior to taking an astrophotograph, you have to align your scope to Polaris, the North Star if you live above the equator. If you live south of the equator, I don't know what you do. Anyway, Polaris is almost exactly aligned with the Earth's polar axis. But when you're taking long exposures, "almost exactly" is not close enough. You have to use a paddle and an eyepiece with an illuminated reticle, plus the off-axis guider to keep the scope centered exactly on the object you're photographing. Or at least that was the old school way of doing it. I suspect most everyone who's into astrophotography nowadays is stacking. _________________ Michael
My Gear List: http://michaelmcbroom.com/photo/gear.html
My Gallery: http://michaelmcbroom.com/gallery3/index.php/
My Flickr Page: https://www.flickr.com/photos/11308754@N08/albums
My Music: https://soundcloud.com/michaelmcbroom/albums
My Blog: http://michaelmcbroom.com/blogistan/ |
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