Search found 252 matches

by chris_ma
Sat Oct 17, 2020 1:37 pm
Forum: Equipment Discussions
Topic: Canon DSLR discounts
Replies: 9
Views: 311

Re: Canon DSLR discounts

Thanks for the comment on the 'cancellation' of the AA filter in the 5DS-R - I thought it was removed, not some software attempt to counter it. I haven't double checked, but I would imagine it's cancelled optically by a second filter in front of the OLPF glas. at least that's how it's done in the D...
by chris_ma
Sat Oct 17, 2020 1:28 pm
Forum: Equipment Discussions
Topic: Micro-Symmar 3.5x
Replies: 30
Views: 760

Re: Micro-Symmar 3.5x

Do you mean the Micro-Symmar 3.5x? For sure the Rayfact 3.5x outperforms both the 105IXL3p5x and the 50MS3p5x. no, I meant the Linos 128DFHR and the Mejiro FEH320 (the last two data sheets linked above), sorry for being ambivalent. from the data sheets to me it seems like they all would perform ext...
by chris_ma
Sat Oct 17, 2020 5:47 am
Forum: Equipment Discussions
Topic: Micro-Symmar 3.5x
Replies: 30
Views: 760

Re: Micro-Symmar 3.5x

are these results to be expected based on the MTF's in the spec sheet?... the micro-symmar 3.5x when compared with the macro-symmar 5.6/80 1x show significantly reduced performance (results that is at the rated/designed magnification scale for each lens). or am I reading this incorrectly? MTF curve...
by chris_ma
Sat Oct 17, 2020 2:49 am
Forum: Equipment Discussions
Topic: Micro-Symmar 3.5x
Replies: 30
Views: 760

Re: Micro-Symmar 3.5x

Robert has some combos for stacked lenses around 3.5x with great performance on his site. most likely the corner performance, flat field and distortion wont be as good as on the RF 3.5x though. edit: as for medium format tube lenses: the Contax 140mm is a fantastic lens on it's own and the Hasselbla...
by chris_ma
Sat Oct 17, 2020 2:47 am
Forum: Equipment Discussions
Topic: Canon DSLR discounts
Replies: 9
Views: 311

Re: Canon DSLR discounts

I agree. first question should be do you really need 50MP? then do you have lenses that are sharp enough, can you handle the data load etc? are you ok with the mirror slap? do you really want to invest in another system which probably wont get many updates? it's certainly a good value, but personall...
by chris_ma
Fri Oct 16, 2020 2:28 am
Forum: Equipment Discussions
Topic: New Mitutoyo apo 10x
Replies: 36
Views: 1008

Re: New Mitutoyo apo 10x

I agree that it's hard to compare images, what a test target could help with is to get a good comparison guideline for "overall system performance", that is, lens, lighting, stray light, mounting, camera sensor etc. even there it will have it's limitations (like a setup which tests well on a wafer m...
by chris_ma
Thu Oct 08, 2020 2:53 am
Forum: Equipment Discussions
Topic: Micro-Symmar 3.5x
Replies: 30
Views: 760

Re: Micro-Symmar 3.5x

I was looking into this lens a while ago and from all I could find it's an excellent performer. what is strange is that the datasheet shows MTF curves for F2.3 F2.5 and F3.4 while the lens is labeled as an F2.8 lens. I suspect it should perform about the same as the inspec.x F4/105 with significantl...
by chris_ma
Wed Oct 07, 2020 8:43 am
Forum: Equipment Discussions
Topic: Sigma 105mm F2.8 DG DN MACRO Art
Replies: 8
Views: 299

Re: Sigma 105mm F2.8 DG DN MACRO Art

rjlittlefield wrote:
Wed Oct 07, 2020 8:37 am
Sounds interesting! Do you have a link to that talk?
it's in the youtube video I've linked in the first message:
https://www.youtube.com/watch?v=zoMLAvZ9Wbw

they have quite a few nice lens diagrams etc
chris
by chris_ma
Wed Oct 07, 2020 1:40 am
Forum: Equipment Discussions
Topic: Sigma 105mm F2.8 DG DN MACRO Art
Replies: 8
Views: 299

Sigma 105mm F2.8 DG DN MACRO Art

Most of you probably have already heard, Sigma released a new Macro in the Art series, the 105mm F2.8 DG DN MACRO Art. sigmas info site: https://www.sigma-global.com/en/lenses/cas/product/art/a020_105_28/ they have a info video on youtube as well (a bit bumpy but very informative): https://www.youtu...
by chris_ma
Fri Sep 18, 2020 6:28 am
Forum: Equipment Discussions
Topic: Schneider macro varon 85/4.5 CAS @1x &2x
Replies: 20
Views: 3603

Re: Schneider macro varon 85/4.5 CAS @1x &2x

I believe the Rodenstock is the same lens as the Linos Float 105/5.6, as Ray mentioned there are fixed mag versions of those on ebay that are quite affordable, and those are very good lenses (I have the 0.33x, 0.5x and 1x). I never tried the Float version, but the MTF on the data sheets look quite a...
by chris_ma
Sun Sep 06, 2020 10:32 am
Forum: Equipment Discussions
Topic: Moisture in my Raynox lens. Suggestions?
Replies: 18
Views: 1631

Re: Moisture in my Raynox lens. Suggestions?

If it condensed water (ie pure water) then just putting it on a heater radiator for a couple of days could help a lot. I got rid of water droplets in an expensive big zoom lens this way. If it‘s dirty water then you‘d have to dismantle the lens and clean the lens elements, chances are that it wont p...
by chris_ma
Fri Sep 04, 2020 3:47 am
Forum: Equipment Discussions
Topic: Thorlabs ITL200 adapters help needed
Replies: 45
Views: 3053

Re: Thorlabs ITL200 adapters help needed

I went through similar calculations when putting together my thorlabs setup, ended up having to order some more parts later on, so it‘s easier to just order some stuff and if it doesn‘t work order another part or two unless you are totally broke or enjoy planning things for ever (I‘m guilty of that ...
by chris_ma
Tue Sep 01, 2020 9:38 am
Forum: Equipment Discussions
Topic: smaller sensor to use lower mag objectives?
Replies: 8
Views: 939

Re: smaller sensor to use lower mag objectives?

Well, if the sensor is 5 to 6 times smaller then you‘d need lower mag lenses, like 0.3x to 1x if I understood things properly.

So the M5400 lens reversed should be truly excellent and resolve a lot of detail even on small pixels.
by chris_ma
Tue Sep 01, 2020 6:51 am
Forum: Equipment Discussions
Topic: smaller sensor to use lower mag objectives?
Replies: 8
Views: 939

Re: smaller sensor to use lower mag objectives?

Not sure I understand this correctly... do you want to keep the same FoV as with your FF sensor or the same as the FF cropped? Because for the former you‘d need lenses with different magnification, for the latter your idea could work, but the Pi camera might not have terribly good dynamic range nor ...
by chris_ma
Tue Aug 18, 2020 8:33 am
Forum: Equipment Discussions
Topic: Full Frame or Medium Format?
Replies: 46
Views: 3471

Re: Full Frame or Medium Format?

I use the 8 exposure high-res pixelshift mode on the S1R. Shooting tethered, it takes about 20sec to show up on the computer. Slower then the K-1, but higher resolution and even less noise. I agree that most people dont really need this level of detail for making lovely images, in my case it‘s more ...