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Astro Berlin C Tachar 125mm f2.3 Lens
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PostPosted: Mon Jun 03, 2019 3:24 am    Post subject: Astro Berlin C Tachar 125mm f2.3 Lens Reply with quote

Bought this lens head on eBay, it has about 95mm focal flange distance. I added a Rafcamera M82.5-M65 adapter, and M65-M65 25-50mm adjustable helicoid, then M65-M42, M42-Nikon adapters, get it working with infinity and close distance focus on Nikon D600 (very big ). Because the 95mm FFD, it could be mounted on many cameras.

Here are some shots, without editing.

@f2.3, f5.6 and f8:

#1


#2


#3


#4


#5


#6


#7


#8


#9


#10


#11


Last edited by cellotone on Sun Jun 09, 2019 2:41 am; edited 2 times in total


PostPosted: Mon Jun 03, 2019 4:31 am    Post subject: Reply with quote

Never seen such a lens before ,the results are nice ,especially the first one wo


PostPosted: Mon Jun 03, 2019 5:21 am    Post subject: Reply with quote

kiddo wrote:
Never seen such a lens before ,the results are nice ,especially the first one wo


Thank you! Not sure what it was originally used for, it doesn't come with the rear barrel part. This focal length maybe good for portrait, I will try to take some portrait shots.


PostPosted: Mon Jun 03, 2019 5:37 am    Post subject: Reply with quote

Somehow the #4 seems not focused but the camera focusing green dot was on. Still learning.

Last edited by cellotone on Tue Jun 04, 2019 5:29 pm; edited 1 time in total


PostPosted: Mon Jun 03, 2019 11:37 am    Post subject: Reply with quote

cellotone wrote:
Not sure what it was originally used for, it doesn't come with the rear barrel part.


They were produced with several mounts, both for stills and film cameras. Here:

http://www.exaklaus.de/astro.htm

you can find a few examples of the 2,3/125 with Exakta mount.


PostPosted: Mon Jun 03, 2019 6:28 pm    Post subject: Reply with quote

@ dickb, thank you for the info! It has very large lenses on both ends. According to the seller, the infinity image size is 82X50mm, I think it probably could cover medium format size cameras' sensors.

Last edited by cellotone on Mon Jun 03, 2019 6:52 pm; edited 1 time in total


PostPosted: Mon Jun 03, 2019 6:39 pm    Post subject: Reply with quote

Really nice shots. Great colors. I see what appears to be a bit of microcontrast washout in the center of number 5. Though that may just be an optical illsusion. I tend to get that with certain adapter/lens combos. The PIXCO helicals are the worst, especially with my asahi pentax 50mm macro.


PostPosted: Mon Jun 03, 2019 6:48 pm    Post subject: Reply with quote

jamaeolus wrote:
I see what appears to be a bit of microcontrast washout in the center of number 5. Though that may just be an optical illsusion.


You are right, there were several pictures showed same, I haven't found what caused that yet. The helicoid used on it is an eBay non-brand name, Chinese made helicoid.


PostPosted: Mon Jun 03, 2019 7:03 pm    Post subject: Reply with quote

cellotone wrote:
@ dickb, thank you for the info! It has very large lenses on both ends. According to the seller, the infinity image size is 82X50mm, I think it probably could cover medium format size cameras' sensors.


On the site I linked to from our member Exaklaus you can find this ad

So 125/2.3 lenses were offered with 6x6 mounts.


PostPosted: Mon Jun 03, 2019 7:11 pm    Post subject: Reply with quote

jamaeolus wrote:
Really nice shots. Great colors. I see what appears to be a bit of microcontrast washout in the center of number 5. Though that may just be an optical illsusion. I tend to get that with certain adapter/lens combos. The PIXCO helicals are the worst, especially with my asahi pentax 50mm macro.


Many adapters and tubes cause some amount of internal reflection. For the best results, flocking the shiny insides with a proper antireflection surface helps a lot. Protostar is used often in astro- and microphotography. I use some sort of plastic tape intended for lining the inside of cupboards, with a black velvet finish. Relatively cheap, but its adhesive isn't quite strong enough for my taste.


PostPosted: Mon Jun 03, 2019 7:13 pm    Post subject: Reply with quote

So 125/2.3 lenses were offered with 6x6 mounts.[/quote]

Thank you! Very detailed info!


PostPosted: Mon Jun 03, 2019 7:20 pm    Post subject: Reply with quote

Many adapters and tubes cause some amount of internal reflection. For the best results, flocking the shiny insides with a proper antireflection surface helps a lot. Protostar is used often in astro- and microphotography. I use some sort of plastic tape intended for lining the inside of cupboards, with a black velvet finish. Relatively cheap, but its adhesive isn't quite strong enough for my taste.[/quote]

Will check inside, do you think paint with black metal paint is ok? Thank you for the reminder, suggestion!


PostPosted: Mon Jun 03, 2019 7:36 pm    Post subject: Reply with quote

cellotone wrote:
Will check inside, do you think paint with black metal paint is ok? Thank you for the reminder, suggestion!


You're welcome. And no, black paint won't help. The problem isn't that the colour isn't black enough, the problem is that that the surfaces are too shiny, too reflective. Flat surfaces are the worst, that is why manufacturers create rings on the inside of optical parts. This in an attempt to create some sort of maze for the stray light to get lost in. Those rings work a bit, but proper flocking, with tiny black hairs standing on a black surface, works better.

Here is an in depth discussion about different types of flocking:
http://www.photomacrography.net/forum/viewtopic.php?t=17917&highlight=protostar


PostPosted: Mon Jun 03, 2019 10:25 pm    Post subject: Reply with quote

A catch!

I agree in this case probably a medium format application originally.


PostPosted: Mon Jun 03, 2019 11:47 pm    Post subject: Reply with quote

dickb:
"You're welcome. And no, black paint won't help. The problem isn't that the colour isn't black enough, the problem is that that the surfaces are too shiny, too reflective. Flat surfaces are the worst, that is why manufacturers create rings on the inside of optical parts. This in an attempt to create some sort of maze for the stray light to get lost in. Those rings work a bit, but proper flocking, with tiny black hairs standing on a black surface, works better.

Here is an in depth discussion about different types of flocking:
http://www.photomacrography.net/forum/viewtopic.php?t=17917&highlight=protostar[/quote]"

@ dickb: Thank you very much! Is this product?

https://www.ebay.com/itm/ScopeStuff-FLK1-Black-Flocking-Material-Self-Adhesive-1-ft-x-47-inches-/271442381228?_trksid=p2385738.m4383.l4275.c10


Last edited by cellotone on Mon Jun 03, 2019 11:50 pm; edited 1 time in total


PostPosted: Mon Jun 03, 2019 11:49 pm    Post subject: Reply with quote

luisalegria wrote:
A catch!

I agree in this case probably a medium format application originally.


Thank you! Like 1 small


PostPosted: Tue Jun 04, 2019 12:28 pm    Post subject: Reply with quote

cellotone wrote:
@ dickb: Thank you very much! Is this product?

https://www.ebay.com/itm/ScopeStuff-FLK1-Black-Flocking-Material-Self-Adhesive-1-ft-x-47-inches-/271442381228?_trksid=p2385738.m4383.l4275.c10


It isn't the exact same product, but it looks extremely similar. It will probably work quite well. In the thread I linked to there are a couple of products that may work even better.


PostPosted: Tue Jun 04, 2019 2:12 pm    Post subject: Reply with quote

Like 1 small Like 1 small Like 1 small


PostPosted: Tue Jun 04, 2019 2:15 pm    Post subject: Reply with quote

dickb wrote:
cellotone wrote:
@ dickb: Thank you very much! Is this product?

https://www.ebay.com/itm/ScopeStuff-FLK1-Black-Flocking-Material-Self-Adhesive-1-ft-x-47-inches-/271442381228?_trksid=p2385738.m4383.l4275.c10


It isn't the exact same product, but it looks extremely similar. It will probably work quite well. In the thread I linked to there are a couple of products that may work even better.


Like 1 small

This is what I have used from the same seller. Flocked all of my adapters, sensor box and the backside of old shiny lenses.

Shipped as a generous large roll with an instructions page.

The adhesive backing is paper like and pressure sensitive, which can make working with a little bit tricky.

I used a fresh X-Acto and vinyl cutting board while held straight under a clear ruler. This will leave a smooth edge - not frayed.

The edges will show up white on any overlap. Which the instructions mention that is insignificant compared to the benefit of flocking. However, you can lightly apply a felt pen with waterproof india ink along the seems for cover up.

Any lint cleans up nicely with sticky tape. Can be removed with ISO alcohol. Don't forget to prep surfaces and remove oils or you will have peel off.

Most important, try to not get it near threaded parts or the backside of bayonets or tight fitting areas. This is where trouble starts.

Applying the material to the inside of an adapter with an opening around 30mm can be very frustrating compared to say a telescope. What I have to do is only unlock a small section of the backing then roll it up to fit into the adapter. You can also roll it into a pencil. Then carefully pull the backing off as the flocking material is applied small sections at a time.

Keep in mind that it will want to not be straight and might pull off the inside of the adapter surface while applying. In these cases it is better to just work in small patches instead of trying to use a single full sized cut.


PostPosted: Tue Jun 04, 2019 5:39 pm    Post subject: Reply with quote

dickb wrote:
cellotone wrote:
@ dickb: Thank you very much! Is this product?

https://www.ebay.com/itm/ScopeStuff-FLK1-Black-Flocking-Material-Self-Adhesive-1-ft-x-47-inches-/271442381228?_trksid=p2385738.m4383.l4275.c10


It isn't the exact same product, but it looks extremely similar. It will probably work quite well. In the thread I linked to there are a couple of products that may work even better.


Thank you! Like 1


Last edited by cellotone on Tue Jun 04, 2019 5:47 pm; edited 1 time in total


PostPosted: Tue Jun 04, 2019 5:45 pm    Post subject: Reply with quote

Blazer0ne wrote:


Like 1 small

This is what I have used from the same seller. Flocked all of my adapters, sensor box and the backside of old shiny lenses.

Shipped as a generous large roll with an instructions page.

The adhesive backing is paper like and pressure sensitive, which can make working with a little bit tricky.

I used a fresh X-Acto and vinyl cutting board while held straight under a clear ruler. This will leave a smooth edge - not frayed.

The edges will show up white on any overlap. Which the instructions mention that is insignificant compared to the benefit of flocking. However, you can lightly apply a felt pen with waterproof india ink along the seems for cover up.

Any lint cleans up nicely with sticky tape. Can be removed with ISO alcohol. Don't forget to prep surfaces and remove oils or you will have peel off.

Most important, try to not get it near threaded parts or the backside of bayonets or tight fitting areas. This is where trouble starts.

Applying the material to the inside of an adapter with an opening around 30mm can be very frustrating compared to say a telescope. What I have to do is only unlock a small section of the backing then roll it up to fit into the adapter. You can also roll it into a pencil. Then carefully pull the backing off as the flocking material is applied small sections at a time.

Keep in mind that it will want to not be straight and might pull off the inside of the adapter surface while applying. In these cases it is better to just work in small patches instead of trying to use a single full sized cut.


Thank you! Like 1
Thank you for the very detailed information of the product and how to use it. Great info, appreciated!!


PostPosted: Tue Jun 04, 2019 5:46 pm    Post subject: Reply with quote

kds315* wrote:
Like 1 small Like 1 small Like 1 small


Thank you Klaus!


PostPosted: Tue Jun 04, 2019 6:53 pm    Post subject: Reply with quote

cellotone wrote:

Thank you! Like 1
Thank you for the very detailed information of the product and how to use it. Great info, appreciated!!


Welcome Turtle