Soligor 300 m f/5.5

[enricosavazzi]

Just for fun, I tested one of the Soligor 300 mm f/5.5 that have been rattling around in my drawers, before packing it up for the next house move. I have also a different one, which I did not test because I don't have an Exakta to Sony adapter.

 

http://www.savazzi.net/photography/soligor300.htm

 

The main surprise is that its overall amount of UV transmission with the Baader U, for practical purposes, is the same as the Coastalopt 60 mm Apo. It does lose a little roughly between 370 nm and 350 nm, but not more than one stop. Not specifically tested at lower wavelengths because I have no suitable filters of the required size.

[Andy Perrin]

Nice! (Imagining that enormous lens on my tiny Sony A7S is making me chuckle.) One suggestion: you assessed the false colors using the histogram; an alternative might be to transform the image to the Lab color space. The b channel is a yellow-blue axis so might allow direct comparisons more easily.

[enricosavazzi]

Nice! (Imagining that enormous lens on my tiny Sony A7S is making me chuckle.) One suggestion: you assessed the false colors using the histogram; an alternative might be to transform the image to the Lab color space. The b channel is a yellow-blue axis so might allow direct comparisons more easily.

It is not so big actually, 23 cm long and about 6.4 cm diameter, under 1 kg I would guess. Much smaller than a typical 300 mm f/4.

[nfoto]

I have a Petri 300mm f/5.5 with about the same UV transmission. However, its UV-imaging capacity is more limited due to pronounced colour aberrations.

 

I concur with Enrico that a 300/5.5 is much smaller and lighter than the typical 300mm class heavy telephoto lens.

[Cadmium]

I think most of the telephoto Petri lenses are made by Lentar, or by whoever made the Lentar brand. I have more than a few of each brand in the same focal lengths and they all seem transmit UV well, better than the Nikon Q 200mm for example.

Here is a pic of a Lentar 200 I have which looks to be quite similar to the Soligor you show.

I can't find a Sparticle test for this 200, but I found a UV test shot and UV test comparison to other longer lenses in my collection at that time.

 

 

 

[dabateman]

Cadmium,

I will haveto see if I can find the old manual film thread. But I remember there being two types of Lentar lenses. The ones with orange numbers like yours were allegedly made by Tokina. The other one I can't remember, but were not as sharp or desirable on the used market.

[Cadmium]

I should make a photo physically comparing all my telephoto Lentar and Petri lenses, but I don't have one to show now.

The 200mm I show above has a different style and look to it that the others, such as the 400mm and 450mm, and others.

From the test shots, I would say that the 400mm and 450mm probably transmit UV slightly better than the 200mm, just from the color, hard to say.

The 200mm does look fairly sharp to me.

The 400mm Lentar is exactly the same as the 400mm Petri, same exact body. They both work the same for UV. They are essentially the same lens other than branding and mount.

[Mark Jones]

i've never seen a lens with an aperture ring at the front before.

most of the 300mm 5.5 lenses on ebay have the aperture ring at the rear, so probabaly a difficult optical formula?

https://www.ebay.com/sch/i.html?_from=R40&_nkw=Soligor+300+5.5&_sacat=0&_sop=15

[Mark Jones]

surprised regular glass can be at effcient at transmitting UV light as a quartz $6000 camera lens? Quartz seems over priced then unless you really need the uvc range.

[ulf]

surprised regular glass can be at efficient at transmitting UV light as a quartz $6000 camera lens? Quartz seems over priced then unless you really need the uvc range.

 

There are many types of "regular" optical glass used in lens design beside other more exotic materials.

Only some of them are transmitting a bit into the UV range.

There are many other aspects making a lens a good UV-lens beside the spectral range and those expensive Quartz-lenses are designed and optimised to work well in their full spectral range.

The reason for the high prices is a combination of high production costs due to small production-volumes, with hand-built lenses with very high precision demands.

The market for these lenses is mainly in the professional area where such prices are acceptable to get a lens that have a well defined function beyond the needed range.

 

Accidental UV-capable lenses might have enough spectral range, but there are often other optical aberrations that can cause problems or degrade the image quality.

 

 

That full spectral UV-range found in a UV-Nikkor 105mm lens is never used on a normal camera, even if it is monochrome-converted. The digital image-sensors used in normal cameras lose sensitivity long before UV-C.

[Andy Perrin]

Mark, a lot of the reason we spend so much time around here looking for "accidental" UV lenses is that so many things affect UV transmission, including number of lens elements, the exact glass composition, and adhesives. However the main thrust of what you said is true — a good "accidental" lens can be nearly as good as quartz for our purposes. But as Ulf said, lens aberrations matter too. You can even have a quartz lens that is terrible if there is large focal shift across the UV-A spectrum, or various types of chromatic aberration, which makes color fringes. When you buy one of those $6000 lenses, you aren't just buying quartz, you're buying a well-designed high quality lens that isn't just coincidentally good for UV, it's designed for it.

[Mark Jones]

Perhaps, but when you pay $6000 for a lens you expect it not to have hot spots.

When you paid $25 a roll of color IR slide film you expect kodak to not use felt on the 35mm roll that is basically white in infrared. You would think Kodak would just use black absorbing NIR felt instead of telling one to change the film in a black bag

and aren't there several apo lenses that claim sharp focus from normal to IR light, but yet use black anodized aluminum internals, which are basically silver with IR light causing ghosting?

 

Just some examples of accidents that shouldn't happen, lol.

[Andy Perrin]

Um, I don't really know what you are getting at there. I thought we were talking about why some lenses are expensive. If you buy an expensive lens that is a cruddy lens, obviously you should return it.

[Mark Jones]

lol, ignore my rants, Just think the coastal optics 60mm lens with hot spots issue should be fixed given it's cost.

[Andy Perrin]

I think you are probably misunderstanding the issues with that lens. I don't have one, so the right person to weigh in on this is someone with one, but I suspect it's impossible to make a lens that doesn't hotspot with every conceivable filter. It's not JUST a function of the lens, in other words. So for example, Andrea had issues with a 340nm bandpass filter and (whatever lens it was she was using). That does not make it a bad lens, it's just that the filter is really shiny.

[Cadmium]

Here is what Boon said about the Coastal Optics 60mm hotspot:

http://myphotojourney.co.uk/review-sony-a7r-coastal-optics-60mm-f4-apo-page-2/

[dabateman]

I think Andrea has been very unlucky with hotspots on that lens. Whereas some others have found work arounds to solve the problem.

I am hoping the 60mm macro c-mount I have coming doesn't have issues but will not know until tested.

You can look at UKA optics quartz lenses. They are realatively cheap. At under $2000, the c-mount 25mm may still be $600. But they have a coatings to only support one specific wavelength. So they will have odd aberrations. Cost goes up from there to increase the range and sharpness of the lens.

[enricosavazzi]

I think you are probably misunderstanding the issues with that lens. I don't have one, so the right person to weigh in on this is someone with one, but I suspect it's impossible to make a lens that doesn't hotspot with every conceivable filter. It's not JUST a function of the lens, in other words. So for example, Andrea had issues with a 340nm bandpass filter and (whatever lens it was she was using). That does not make it a bad lens, it's just that the filter is really shiny.

I agree. Then there is the specific problem that a UV+VIS+IR lens must have AR coatings that work in all three bands. Unfortunately, multicoatings cannot be optimized for minimum reflectance in a broad band. They can be optimized for very low reflectance (around 0.1% per optical surface) in a relatively narrow band (only VIS for example) and a high reflectance in UV and IR, or a moderately high reflectance (roughly 0.5 to 1%) across a band roughly twice as broad. CoastalOpt chose the latter alternative, which is reasonable for a multi-band lens. A high reflectance of the coatings is one of the factors that can invite flare (although not as bad as no coatings or single-layer coatings).

 

In the large majority of cases, a lens shade appropriate to the focal length and sensor size greatly reduces the risk of flare, except when contrast must be greatly increased in post-processing, or when overexposing, or when illumination directly strikes the filter or front element of the lens.

 

My experience with this lens:

http://savazzi.net/photography/coastalopt_60.html

http://savazzi.net/photography/coastalopt_60_hotspot.html