Home

Please support mflenses.com if you need any graphic related work order it from us, click on above banner to order!
SearchSearch MemberlistMemberlist RegisterRegister ProfileProfile Log in to check your private messagesLog in to check your private messages Log inLog in

Infrared Hotspot lens tests
Post new topic   Reply to topic
Home   Manual Focus Lenses
View previous topic :: View next topic  


PostPosted: Sat May 19, 2007 5:08 pm    Post subject: Infrared Hotspot lens tests Reply with quote
This A.M. I tested eight lenses for the dreaded infrared hotspot, Russian and Japanese glass, seven M42 mount with adapters and one Mamiya with adapter.
For those unaware if this issue, many lenses will show a sometimes large bright circle in the center of an image when shooting infrared images.

I’m happy to say that none of the lenses showed any hotspot whatsoever.

The lenses are:

Jupiter 21A
Helios 28 (Japanese)
Helios 44M-4
Super Takumar 28
Jupiter 9
Takumar 135
Mamiya 80 (645 lens)
Sears 90-230

I tested each lens wide open, at F8, and at f16.
These were all used on an unmodified Canon 30D with exposure times of from two seconds to thirty seconds depending on sunlight and lens speed which varied from F2 to F4.5 wide open.
Hoya R72 filter

Target test area, bamboo and fig plants : (Helios 44M-4 infrared shot)



Cheers

Jules


PostPosted: Sat May 19, 2007 5:56 pm    Post subject: Reply with quote
Interesting test! Thanks a lot!


PostPosted: Sat May 19, 2007 8:50 pm    Post subject: Reply with quote
Jules, how can you shoot infrared on a digital camera ???


PostPosted: Sat May 19, 2007 9:14 pm    Post subject: Reply with quote
LucisPictor wrote:
Interesting test! Thanks a lot!


Thank you Carsten, It's great fun to do.

Jules


PostPosted: Sat May 19, 2007 9:15 pm    Post subject: Reply with quote
Orio wrote:
Jules, how can you shoot infrared on a digital camera ???


Hi Orio,

It’s not difficult at all. I’ve been shooting IR with film and digital for some years now. Rather than repeat a lot of information my friend Jerry Kneupper has an excellent site that explains step by step how to do it in the article, “Infrared for Beginners Series”.


http://www.irbuzz.blogspot.com/

(Basically all you need is an IR pass/visible block filter and a tripod (many cameras require long exposures, 2 to 30 secs)

and here is a more technical look at IR photography in general

www.infraredphoto.eu/IR_Paper_Part_One.htm

I have “the” Yahoo IR group,

http://groups.yahoo.com/group/Infrared_Photography/

Come visit to see some of our member’s very interesting IR digital work.

Cheers

Jules
Post new topic   Reply to topic
Home   Manual Focus Lenses
Page 1 of 1