Search found 181 matches
- Tue Oct 15, 2019 11:49 am
- Forum: Equipment Discussions
- Topic: COB Ringlight
- Replies: 39
- Views: 5958
Another pleasant surprise today from my postman: 30, 40 and 45mm COB ring lights arrived so I immediately did (guess what) measuring and testing! http://www.photomacrography.net/forum/userpix/3435_DSCF6459_1.jpg They contain 16, 20 and 24 led elements behind layer of phosphor. I measured 5600K with ...
- Tue Oct 15, 2019 1:49 am
- Forum: Equipment Discussions
- Topic: $2.50 Rogonar-S v $250 APO-Rodagon-D v $1K Canon MPE Test
- Replies: 32
- Views: 5077
Rodenstock 75mm f4.5 APO-Rodagon-D 2x
Thank you for another inspirative comparison, Robert. Your ability to dig less known lenses from the dark side is incredible as well as the feeling for possible above average results from such specimen. This time you've decided to compare to "well known Rodenstock APO-Rodagon-D 2x". Yes, I have one ...
- Mon Oct 14, 2019 11:32 am
- Forum: Equipment Discussions
- Topic: COB Ringlight
- Replies: 39
- Views: 5958
Here is another one, just arrived today in a form of carabiner keychain flashlight. Built-in cob element has 23mm o.d and 12mm i.d., sounded great for microscope objectives lighting. Although there are 6 LED elements only, they emit huge amount of nicely spread light, drawing 0.53A at full power or ...
- Fri Oct 11, 2019 8:50 am
- Forum: Equipment Discussions
- Topic: Comparing macro lenses using MTF - invitation, take 2
- Replies: 26
- Views: 6164
List correction
Christian has just posted me slight naming correction: Lens #1 is actually Reflecta iScan 3600 and the lens #2 is actually Reflecta CrystalScan 7200. I wonder what are the differences to ProScan 7200....
- Fri Oct 11, 2019 7:02 am
- Forum: Equipment Discussions
- Topic: Comparing macro lenses using MTF - invitation, take 2
- Replies: 26
- Views: 6164
Comparing macro lenses using MTF - invitation, take 2
Last week our fellow photomacrographer Christian (Typestar) from Austria has kindly send me huge pile of lenses for MTF testing. No less than 28 pieces ranging from tiny 9g Rodagon 31mm f5.6 to 925g giant Kodak scanner lens. This is how they look when put together in front of camera: http://www.phot...
- Fri Sep 27, 2019 6:44 am
- Forum: Equipment Discussions
- Topic: Comparing macro lenses using MTF - invitation
- Replies: 18
- Views: 5747
Is there a way to replicate your setup or is there any special gear/test target needed? chris Nothing really special here: Fuji X-T2 mounted on motorized macro rail, backlit double edge razor blade slanted at ~6 degrees, shot approx. 30 raw frames at 1/10 DoF movement. Raw to tiff conversion using ...
- Fri Sep 27, 2019 6:32 am
- Forum: Equipment Discussions
- Topic: Comparing macro lenses using MTF - invitation
- Replies: 18
- Views: 5747
I understand that it is very complicated to have several bodies with their adapters, but, for example: Do you have any comparative measurement of the same lens mounted on the different APSC sensors of the Fuji series (16, 24 or 26 Mpx) ?. The best You should keep in mind I'm doing all those test fo...
- Fri Sep 27, 2019 12:25 am
- Forum: Equipment Discussions
- Topic: Comparing macro lenses using MTF - invitation
- Replies: 18
- Views: 5747
Thank you Filip for the nice words. Measuring lenses the MTF way is both fun and useful activity IMHO. Since I have tested dozens of lenses and didn't publish all the results here (those are contained within one gigantic spreadsheet), I'm considering cutting it into smaller chunks and publish them w...
- Mon Sep 23, 2019 2:29 am
- Forum: Equipment Discussions
- Topic: Microscope fan cooled illuminator
- Replies: 2
- Views: 693
Saul, my advice based on experience is: keep fans as further away as possible from macro rail. Six years ago I was fighting blurry stacks and the cause were fans mounted on my diy led lights: https://www.photomacrography.net/forum/ ... highlight=
- Sun Sep 22, 2019 1:19 pm
- Forum: Equipment Discussions
- Topic: Comparing macro lenses using MTF-Part IX: Some budget lenses
- Replies: 11
- Views: 3794
Filip, I'm glad you find my MTF tests useful. I believe you are dissapointed with some results and have feeling those lenses/objectives produce fine pictures. And they will untill you find something better. That's how it goes in this hobby! I thank you for doing this effort and expense for sending m...
- Sat Sep 21, 2019 5:16 am
- Forum: Equipment Discussions
- Topic: Comparing macro lenses using MTF-Part IX: Some budget lenses
- Replies: 11
- Views: 3794
Three scanner lenses
Next 3 lenses Filip has send me for testing are very different scaner optics. http://www.photomacrography.net/forum/userpix/3435_Scanner_lenses_1.jpg The smallest one was taken from Minolta Dimage Dual Scan (F-2400). I have measured it as 33mm f/5.6. Tested it both direction, reverse orientation giv...
- Fri Sep 20, 2019 12:34 am
- Forum: Equipment Discussions
- Topic: COB Ringlight
- Replies: 39
- Views: 5958
- Wed Sep 18, 2019 1:16 am
- Forum: Equipment Discussions
- Topic: COB Ringlight
- Replies: 39
- Views: 5958
This 30mm variety could be nice fit between half of ping pong ball and objective front surface. If glued together it steals less than 1 millimeter from the working distance. In case of excessive heat, one could use this heatsink mounted reversed and fan removed: https://www.aliexpress.com/item/33053...
- Mon Sep 16, 2019 11:38 pm
- Forum: Equipment Discussions
- Topic: COB Ringlight
- Replies: 39
- Views: 5958
There are other small COB ring light sources, such as this one: https://www.ebay.com/itm/Mini-Carabiner-Light-Flashlight-Led-Keychain-Outdoor-Portable-Flashlight-Night/173874803930?hash=item287bbef4da:g:ZJQAAOSwqYRctcOA It has only 6 light sources and probably gives tiny amount of light. But here is...
- Sun Sep 15, 2019 10:26 pm
- Forum: Equipment Discussions
- Topic: Comparing macro lenses using MTF-Part IX: Some budget lenses
- Replies: 11
- Views: 3794