Micro-Symmar 3.5x

[chris_ma]

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 extremely well (ie. close to what is possible at F2.4 at 3.5x), I never saw any MTF curves for the rayfact, but given from what I know about their other lenses and the price, I'd be very surprised if it wouldn't keep up.

I agree there's no point in comparing the 80MS, it won't come even close.

on the 50mm Micro Symmar I'm still confused about the F2.3 Curves (and missing F2.8 curves) in their data sheet, so I have no idea how to interpret that. very unfortunate though that in real world it doesn't perform as you'd hoped.

[RobertOToole]

on the 50mm Micro Symmar I'm still confused about the F2.3 Curves (and missing F2.8 curves) in their data sheet, so I have no idea how to interpret that. very unfortunate though that in real world it doesn't perform as you'd hoped.

Hi Chris,

The data sheet for the Micro-Symmar has been discussed here on the forum before. The MTFs are disappointing but at least SK is honest about what they do show. They just decided to leave a few things out

Schneider industrial lenses sometimes are made to work in a certain wavelength range, that batch of 2.2/50 Xenon lens that came up on Ebay in 2018 or so is a good example. The lens was really poor with full visible light and the MTF showed that, but later I did see the same lens with a notch cut filter and it was a different lens with great MTF curves. I did find a sample of a bandpass filter effect on MTF, this one is the Xenoplan 2.8/50. Couldn't find the 2.2/50 Xenon!

So that micro-symmar might have been designed for machine vision not in white light, and they only decided later to sell it on the general market maybe?

Edit: The MTF I posted earlier was incorrect, it was not B' but 1/B' so -3.85 was really 1/4x. Sorry about that.

[Lou Jost]

Robert, as you know, that is generally true of any lens, a narrow bandpass filter will reduce CA, and completely eliminate it if the bandwidth is narrow enough. But that makes the lens useless for color photogrpahy. Surely SK would have mentioned a restricted wavelength in the specs of the lMicro-Symmar?