A simple planachro comparison.

[apochronaut]

Here is something for you to have a look at, Karl and whoever else is interested, too.

I am a bit surprised that there isn't as much difference in these as there was with the 40X planachros.

The cat.# 1014 100X 1.25 with an iris diaphragm has always seemed a mystery to me. It was one of the earlier 100X planachros that they formulated, going back to the early 70's. One would think that it would have been just a standard cat.# 1024 planachro with an iris but it isn't. It , and the cat.# 1022 20X .50 were the originals classed as advanced planachros, followed in the 80's by several series of others. Whatever they were doing inside that barrel, it worked, because it remains the best of the planachros, even better than the cat.# 1311, which is a tall order. The pink hue in the refractive sections of the structure is ca.

Missing is the cat. # 1029 100X 1.25 Advanced Planachro, which I remember as being a superior objective to the cat.# 1024.

Slide is a 19th century pond debris slide.

[Hobbyst46]

Interesting post, thanks.
I usually use my phase objectives for brightfield as well - but most are neofluar/planapo, so I hope that the effects of the phase ring are weaker.

I wonder if anyone has invented a quantitative non-subjective (as far as possible) slide test + image analysis software that will grade the optics according to some standard rather than the visual impression. Diatom test slides are still qualitative, and IMO are not ideal to show CA for example.

[apochronaut]

You are right about diatoms, in terms of quantitative assessment but they are good subjects for squeezing out refraction and showing how colour corrected an objective is.

[MichaelG.]

I wonder if anyone has invented a quantitative non-subjective (as far as possible) slide test + image analysis software that will grade the optics according to some standard rather than the visual impression. Diatom test slides are still qualitative, and IMO are not ideal to show CA for example.

This doesn't really meet your criteria, but I think it's perhaps a step in the right direction:

Apple 'Retina' display ... Zeiss 4x Planapo used as a macro objective with no eyepiece

IMG_1610.JPG (104.54 KiB) Viewed 3287 times

The display is flat
The pixels have a tightly specified spacing
The sub-pixels have known colours

BUT it's all on too big a scale to be useful for high power objectives.

The search continues !!

MichaelG.

[einman]

Very Nice comparison. Although the pictures are quite good I would tend to accept your personal visual assessment over my opinion of the pics. Pics are rarely as nice as the actual images.

[McConkey]

Thanks for posting this!!
They do all look strikingly similar! Do you happen to know why the 1311 has such an intense red area near the top compared to the others? It looks like the 1129 and 1311 also have better colours and less of a tint. It's a hard press between the 1129 and the 1311...The 1311 appears sharper and with less chromatic abrasion but i think the colours and brightness on the 1129 might be better!

Really interesting comparison especially considering i thought there would be a clear winner!!

Thanks for sharing!!

[apochronaut]

I am not sure why that feature is so red . I didn't notice it on the camera screen.

The pictures are not as representative as they should be. The images were visually much crisper and the impressions of difference, more dramatic. So visually, in the microscope, I would say the 1014 and 1311 are the objectives with an edge in resolution. The 1129 might have an edge in ca control across the field but the 1014 , although having a bit more lateral ca, is the best for ca overall, being almost completely devoid of it centrally.
The 1014 objective was used primarily for DF and fluorescence, where ca is a blight. It seems to be a whole other objective than the 1024, which came out around the same time, being more consistent with planachromat performance for it's day. The high price for the 1014, was probably not entirely accounted for by the presence of it's iris diaphragm but also by it's enhanced advanced planachro performance, which seems a step ahead for the early 70's.

Bear in mind that all that pink/lavender colouration is in fact a ca artifact, and quite consistent with achromat performance . The 1014 has none of it and what ca is present is of a blueish tint, more consistent with what one would expect from a fluorite. Any achromat is going to see ca in the refractive structures, with this sample. Often, ca and diffraction yields an enhanced contrast, which is false contrast. Using an apochromat in comparson to an achromat, more often than not yields a somewhat contrastless or bleached appearance, where the achromat seems more contrasty due to producing optical artifacts. The # 1014 has the cleanest overall image, somewhat fluorite like, albeit with just ever so slightly less resolution than the 1311, which seems best in that regard.