Search found 1309 matches
- Sun Feb 28, 2021 2:33 am
- Forum: Equipment Discussions
- Topic: This Just Seems Strange
- Replies: 12
- Views: 354
Re: This Just Seems Strange
[...] The best? They are asking 40% more than list price for a used lens, the Chinese eBay sellers do this every day. They are asking $1400 for a used lens that is $995 straight from the US distributor new. Lazy sellers. :-k [...] One factor in this (hopefully) self-defeating seller strategy is tha...
- Sat Feb 27, 2021 2:53 pm
- Forum: Equipment Discussions
- Topic: This Just Seems Strange
- Replies: 12
- Views: 354
Re: This Just Seems Strange
If it is any consolation, I regularly see second-hand items on eBay, Aliexpress etc. at prices that significantly exceed the price of the same item in factory-new condition. China-based sellers seem to be especially greedy these days. Some Indian and SE Asian sellers also sometimes seem to have no c...
- Sun Dec 27, 2020 9:28 am
- Forum: Equipment Discussions
- Topic: Sony A7R with microscope lens
- Replies: 32
- Views: 8822
- Fri Dec 18, 2020 1:08 am
- Forum: Macro & Microscopy Articles
- Topic: Some progress toward NLOS imaging
- Replies: 1
- Views: 863
Some progress toward NLOS imaging
Report stating that non-line-of-sight imaging is about to become usable:
https://www.laserfocusworld.com/detecto ... 0965823D2G
https://www.laserfocusworld.com/detecto ... 0965823D2G
- Sat Dec 12, 2020 3:15 am
- Forum: Equipment Discussions
- Topic: Testing Olympus UPlanFL N 4x 0.13 (FN 26.5)
- Replies: 26
- Views: 5044
Re: Testing Olympus UPlanFL N 4x 0.13 (FN 26.5)
[...] It [SWTLU] is cheaper than the U-TLU, which surprises me. There's also a U-SWTLU-SP which is $4075 (yes, four thousand), it uses ecoglass. Not sure if there's a pictorial difference. The fact that the SWTLU is cheaper than the U-TLU is probably explained by the fact that the SWTLU is just an ...
- Thu Nov 26, 2020 11:54 pm
- Forum: Equipment Discussions
- Topic: Reversed wide angle vs. telephoto for w/a macro relay
- Replies: 13
- Views: 2590
Re: Reversed wide angle vs. telephoto for w/a macro relay
Nice, 2011 is the earliest use of M12 lenses I've seen did you invented yourself? or can we find someone earlier? For the same use I'm looking for pinhole-type objectives, with forward pupil, maybe wider and with better optics. Marco Cavina described the Zeiss "Sonderobjektiv", a pinhole lens for 3...
- Thu Nov 26, 2020 1:44 pm
- Forum: Equipment Discussions
- Topic: Reversed wide angle vs. telephoto for w/a macro relay
- Replies: 13
- Views: 2590
Re: Reversed wide angle vs. telephoto for w/a macro relay
Years ago I did some work with a relay system, which I described in my 2011 book "Digital photography for science". While the discussion in the book contains additional details, the essential components from front to rear are: - A short-focal-length "pinhole lens" in CS mount (I used both a 2.8 mm f...
- Tue Nov 24, 2020 2:36 pm
- Forum: Equipment Discussions
- Topic: Mitutoyo gamme NIR pour macrophotographie
- Replies: 3
- Views: 1344
Re: Mitutoyo gamme NIR pour macrophotographie
The M Plan Apo NIR series is corrected from 480 to 1800 nm, so they likely display chromatic aberration in the 400-480 nm range (blue and indigo). Anything above 1,000 nm likely cannot be recorded with a Bayer sensor even after removing the NIR- and NUV-cut filters of the camera, so you would be pay...
- Mon Nov 02, 2020 1:03 pm
- Forum: Equipment Discussions
- Topic: Review of Mitakon Creator 85mm f/2.8 1-5X Mark II
- Replies: 10
- Views: 3603
Re: Review of Mitakon Creator 85mm f/2.8 1-5X Mark II
I found this lens's narrative arc very strange. One kind of gets the impression this company has no idea what they're doing, but I almost never follow normal camera lens development so I don't know if this kind of thing is normal? I would not say it is normal, but it is not unheard of either, espec...
- Mon Nov 02, 2020 12:45 pm
- Forum: Equipment Discussions
- Topic: Review of Mitakon Creator 85mm f/2.8 1-5X Mark II
- Replies: 10
- Views: 3603
Re: Review of Mitakon Creator 85mm f/2.8 1-5X Mark II
The redesign caused the nominal aperture to increase from f/2.8 to roughly f/4.8-f/5.6 I would suggest the aperture decreased or was reduced. The way I use the term aperture value in the review is in the sense of f/ratio. This is the aperture as expressed in several of the geometric optics formulas...
- Fri Oct 30, 2020 2:26 pm
- Forum: Equipment Discussions
- Topic: Review of Mitakon Creator 85mm f/2.8 1-5X Mark II
- Replies: 10
- Views: 3603
Review of Mitakon Creator 85mm f/2.8 1-5X Mark II
I have written an in-depth review of the Mitakon Creator 85mm f/2.8 1-5X Super Macro (the Mark II version of this lens) because the reviews I found online do not answer several of my questions about this lens. The text is not final and the page is not yet linked to the rest of my web site, but can b...
- Wed Oct 28, 2020 12:00 am
- Forum: General Discussion Forum and Community Announcements
- Topic: Found mantis - now what?
- Replies: 4
- Views: 1772
Re: Found mantis - now what?
Mantodea are often kept as pets. There is quite a bit of advice on the web, for example https://www.keepinginsects.com/praying-mantis/care/ and links therein.
(at the above link, I could not resist laughing at the misspelling "live in desserts")
(at the above link, I could not resist laughing at the misspelling "live in desserts")
- Wed Oct 14, 2020 9:20 am
- Forum: Equipment Discussions
- Topic: Can I push the resolution of a 1:1 macro lens?
- Replies: 23
- Views: 4773
- Wed Oct 14, 2020 6:32 am
- Forum: Equipment Discussions
- Topic: Can I push the resolution of a 1:1 macro lens?
- Replies: 23
- Views: 4773
Re: Can I push the resolution of a 1:1 macro lens?
[..]In the intro to the article, you mention two of the ways to get higher magnification out of a 1x macro lens, but you leave out what is potentially the best way, reversing it not on extension tubes but on a tube lens. I think it would be a more complete article if you mention that option and its...
- Tue Oct 13, 2020 12:24 am
- Forum: Equipment Discussions
- Topic: Can I push the resolution of a 1:1 macro lens?
- Replies: 23
- Views: 4773
Re: Can I push the resolution of a 1:1 macro lens?
As I explained above, with modern lenses that have floating elements, you should have used a teleconverter instead of extension tubes. Otherwise you aremoving the lens far from ist design point. I just published a page on my site dealing with tests of four legacy macro lenses with a 2x teleconverte...