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Tamron Adaptall-2 SP 500mm f/8 Mirror (55BB)

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24 78,917 Tue August 4, 2020
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100% of reviewers $151.90 8.79
Tamron Adaptall-2 SP 500mm f/8 Mirror (55BB)

Tamron Adaptall-2 SP 500mm f/8 Mirror (55BB)
Tamron Adaptall-2 SP 500mm f/8 Mirror (55BB)
Tamron Adaptall-2 SP 500mm f/8 Mirror (55BB)
Tamron Adaptall-2 SP 500mm f/8 Mirror (55BB) Tamron Adaptall-2 SP 500mm f/8 Mirror (55BB)

"This later version SP 500mm F/8, introduced in 1983, is an optically revised version of the original model 55B lens first introduced in 1979. The major optical design change is the switch to a constant thickness meniscus main mirror in order to reduce close focusing spherical aberration. The change in the main mirror design also necessitated changes for the two smallest lenses located within the middle of the optical design. This model 55BB also discards the earlier model's detachable tripod mount and the set of four filters for B&W photography. The later model 55BB is also readily distinguished from the original model by its diamond knurled rubber focus grip and the lack of the locking screw used on the earlier model 55B's built-in rotating tripod mount ring. Thus this lens does not feature any built-in tripod mount whereas the original lens featured a detachable tripod mount." -

Manufactured from 1983 to 2005... probably the most common 500mm cat. on the market. Easily distinguished from its predecessor the 55B by the square dotted rubber grip and absence of a tripod mount.
This and the other two tamron mirrors (55B, 06B) are designed to be used with a 30.5mm rear filter in situ, this screws on to the end of the rear group at the mount end.
The fixed aperture means that there is no advantage to a PKA mount. any PK mount will do and you can use Av.

Minimum aperture: fixed at f/8. Note that there is a significant difference between f stop and t-stop with mirror lenses.
Elements/groups: 8/5
Minimum focus distance: 170 cm
Maximum magnification: 1:3
Minimum length: 87.0 mm
Maximum length: 91.5 mm (dependent of the adapter)
Diameter: 84.0 mm
Weight: 0.595 kg
Front Filter diameter: 82mm
Rear Filter diameter: 30.5mm (screw-on)
Hood mount: screw-on. Normally comes with deep flock lined metal hood that inverts for storage.

Accepts SP 2X tele-converter #01F and SP 1.4X tele-converter #140F. Note: TC's are reviewed in miscellaneous lenses - TC's.

Good discussion/review of mirror lenses including 06B by Wayne Grundy. And Bob Atkins has also done a detailed comparison with a Canon 500mm f4.5.

U-tube review by Gary Reed (sony apsc, kenko 1.4x tc).

Detailed comparson of 55BB with several other mirrors, including Canon and Nikon, by DCview blog (chinese - google translate)
Mount Type: Third-party (adapter required)
Price History:

Add Review of Tamron Adaptall-2 SP 500mm f/8 Mirror (55BB)
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Loyal Site Supporter

Registered: February, 2014
Location: Pennsylvania
Posts: 1,435
Lens Review Date: August 4, 2020 I can recommend this lens: Yes | Price: $120.00 | Rating: 8 

Pros: Sharp & Contrasty for a Mirror lens, light, small
Cons: Best at closer distances, it’s a mirror lens
Sharpness: 8    Aberrations: 9    Bokeh: 8    Handling: 8    Value: 10    Camera Used: K5iis, K3, KP   

The Tamron Adaptall-2 55BB is probably the best catadioptric “mirror” lens for the average photographer. I’ve owned four CAT lenses, the 55BB, Tokina 500/8, Celestron 500/5.6 and Opteka 500/8. This Tamron is far and away the best, well worth having in ones kit.

Sharpness is very good, I’d have given it an 8.5 if the rating were available. Closeup capability is a strong point- no other 500mm lens that I know of can focus into macro range. The lens is quite hand holdable with proper technique and Pentax DSLR Shake Reduction. You need a body with excellent high ISO performance since the T-stop of this lens is f/10, not f/8. In bright light, contrast is high and colors are saturated. In dull light, images need a boost in both areas.
Out to about 150 feet, this lens is very sharp and images respond well to PP sharpening. Past 150 feet, images begin to degrade somewhat.

Abberations are extremely well controlled, surprisingly good. Bokeh? Well it gives the classic CAT/mirror lens “donut hole” out of focus highlights. Used creatively, this can be fun, otherwise it is a bit distracting.

Please use this lens with the straight Pentax K/M Adaptall-2 adapter and not the PK/A version. The K adapter allows shooting with the camera on Aperture Preferred with no fiddling around. Plus, the K adapter is far less expensive.

I definitely recommend this lens. Small, light, smooth focusing, reasonably sharp and easy to take with you.

Registered: December, 2009
Location: Christchurch, New Zealand
Posts: 2,025
Lens Review Date: October 27, 2019 I can recommend this lens: Yes | Price: $145.00 | Rating: 9 

Pros: Sharp for a mirror, low CA, relatively small and light, bokeh
Cons: bokeh
Sharpness: 8    Aberrations: 10    Bokeh: 7    Handling: 8    Value: 10    Camera Used: K-1   

This is the 3rd 500mm Mirror I have got. The first one was riddled with fungus and not sharp at all, the second was a Opteka 500mm which is very small for a 500mm but average sharpness (although usable for some uses) and really tricky to focus. Then I saw a Tamron for sale and went for it.

Its a lot better than the Opteka and a lot easier to focus too. For me Tamron is a viable telephoto that I can carry due to its compact size and light weight (for 500mm at least). Contrast is not super high but thats a mirror thing in general.

Bokeh can be an advantage and disadvantage. For a start, in the many scenarios (depending on background and distance to background) the bokeh is fine, and when its painting donuts sometimes that can work well in photos too but then it depends on the scene and your point of view.

Overall I'm pleased to have it in my toolkit.

Some samples:
Moon (

Hawk (

Seagull (

Bokeh (
Seeker of Knowledge

Registered: August, 2016
Location: Topeka, Kansas
Posts: 20,627
Lens Review Date: March 19, 2019 I can recommend this lens: Yes | Price: $70.00 | Rating: 8 

Pros: seems well made, sharp, great value
Cons: hood when rversed is friction fit only and does slide off easily, mirror lens problems
Sharpness: 9    Aberrations: 9    Bokeh: 5    Handling: 9    Value: 10    Camera Used: K 3 or K 3 II   

I just got this lens having found it on EBAY and the seller willing to make a deal off of his initial price

does have some visible loss of coatings on lens but on very edges and has no effect on the photos

I like it but there is a learning curve and has the typical mirror lens limitations

so far trying it hand held, braced at times,

no real opportunity yet to use it to its full potential as a true telephoto

Registered: May, 2015
Location: Hampshire
Posts: 891
Lens Review Date: March 12, 2019 I can recommend this lens: Yes | Price: $60.00 | Rating: 10 

Pros: No ca problems, great value for money, adaptall.
Cons: In the review body.
Sharpness: 9    Aberrations: 9    Bokeh: 8    Handling: 10    Value: 10    Camera Used: K-5   

Yet another lens with fungus bringing the cost down, a clean lens would be worth much more than the one I bought.
This was auctioned as having the fungus but was in good condition otherwise and after reading up in the forums about how to clean it I bought it had a go myself. I did not break anything so maybe I was lucky but after the event a forum member in North Wales did point out that the method I used (entry through the front element) could have resulted in a poorer IQ due to the very tight tolerances. Any inexperienced dabblers beware. Thank you Marcus.

I am very pleased with this lens, it may not vie successfully with the better refractive lenses lenses but it is the best 300mm plus lens that I own.
There is no CA apparent as far as I can see , it is quite sharp even hand held! and can be focussed by eye in bright sun quite easily. Not that I would be tempted to use it much without some sunlight.
It has a close focus ability that makes it better than my 300mm plus lenses in that regard.
The ring bokeh can be awful but can also be used for effect.

On the down side, my using it hand held when my aging body is continually moving and my hands tremble does mean some images OOF due to it's small depth of field.

Yet another Tamron SP adaptall that is good. On todays modern digital cameras with focussing aids and ISO 800 plus abilities, it is probably great for it's cost.
There were apparently lots of these sold so no reason to avoid buying one and enjoying it.

Registered: January, 2011
Location: Houston, Texas
Posts: 969
Lens Review Date: May 28, 2018 I can recommend this lens: Yes | Price: $100.00 | Rating: 9 

Pros: Lightweight, very sharp, long focus throw, great hood
Cons: No tripod mount -- although not really necessary

My review is for the Tamron 55BB, but I've seen lots of photos taken with the 55B and it appears to be every bit as good.

I find this lens to be exceptionally sharp for a mirror lens, and also to have better than average contrast. I especially like the 55BB's very long focus throw -- almost a full 360 degrees.

I have found, from my early experiences with a Sigma 600mm f/8 I bought in 1984, at which time I was an advancing amateur, that it takes a fair amount of practice before one can expect to reliably produce good images with a long mirror. There were days way back then that I was convinced that Sigma was junk, but as my technique improved, my impressions of that lens's capabilities improved. You can't just expect to mount this lens and then shoot snaps with it, and expect much from the results. No you need to pay close attention to accurate focus, and because it's a 500mm lens with a fixed f/8 aperture, you need to pay extra special attention to shutter speed and sturdiness of the camera's mount. In many cases, when the shutter speed is low, if your camera has mirror lock-up, it should be used, or in the case of a digital, at a minimum, the self timer should be employed. Paying attention to anything that might induce vibration will reap rewards in the final image.

Here's a shot of the moon taken with the Tamron mirror. The camera as a Sony NEX 7, set to ISO 100. Shutter speed was 1/125. Note that this is not a grayscale image, so the Tamron allows one to see the actual colors of the Moon's surface.

Here is a double image I put together of the crescent moon, showing images taken with my old Century Precision Optics Tele Athenar II 500mm f/5.6 refractor, set to f/8 and the Tamron 55BB. I put the two images together to show how well this mirror stacks up with a very good refractor of the same focal length. There are some white balance differences, and the CPO seems to have just a bit more contrast than the Tamron, but I can't tell a difference regarding sharpness. Image size was adjusted in post processing to take into account the NEX's 1.5x magnification.

I can highly recommend this lens. It can often be found for a very good price these days, and as such, I think it should be a no-brainer since sometimes there is just no substitute for mm's.
New Member

Registered: February, 2012
Posts: 15

2 users found this helpful
Lens Review Date: October 21, 2017 I can recommend this lens: Yes | Price: $55.00 | Rating: 9 

Pros: Light, sharp, adaptall mount gives flexibility
Cons: None
Sharpness: 9    Aberrations: 9    Bokeh: 7    Handling: 10    Value: 10    Camera Used: Samsung GX10, GX20, Pentax K-x   

I bought this lens to fill a gap in my Adaptall collection. I didn't think I needed it, because I was happy with the Samyang 500mm f6.3.

I bought my 55BB eBay. The low price is indicative of the fungus infestation that was clearly visible in the item photos. However, even with the fungus, it was obvious as soon as I looked through the viewfinder that the lens had potential, and it turned out to be fairly easy to clean it up.

The distance scale is held on with 6 grub screws. If you undo these, the scale can be slid towards the mount, exposing the screws that hold the stop on the top half of the lens. Undo these, and the the front section of the lens can be unscrewed. Mark where the two halves separate so you can start the reassembly at the right point.

The cleaning (inside and outside the front element, and the glass over the main mirror), is simple in theory, if tedious.

Xylene (paint thinner) seems to be poisonous to lens fungus, it removes organic non-ionic material, and dries streak-free. Unfortunately it doesn't remove ionic material.

Distilled water removes ionic material, but not grease.

Alternating between the two I gradually ended up with bright clean streak-free scratch-free lens surfaces.

Reassembly was then the disassembly process in reverse. As long as you start the screw-in process from the right point, it all just works.

In addition to his review of this Tamron lens in comparison with a Canon non-mirror lens referenced above, Bob Atkins has this excellent review of the Samyang 500mm f6.3, which also refers to this Tamron.

The Tamron:
  1. Is smaller
  2. Is the same effective speed as the Samyang
  3. Has a larger depth of field
  4. Has slightly better sharpness
  5. Has much better contrast
Hand held I'm hard to pressed to see evidence of point 4, and shooting raw and boosting contrast my pictures from the two lenses become virtually indistinguishable, but points 3 and 5 translate to easier manual focusing of the Tamron.

I have one other mirror lens, the Tokina 500mm f8. This is the smallest, and mechanically the nicest of the three, but it is slower, and not as sharp as the Tamron; it is similar to the Samyang.

The Tamron has one further advantage over the both the Tokina and the Samyang.

All Pentax-K Adaptall mounts have (non-functional for this lens) aperture levers.

This means that, unlike the other two mirror lenses I have used, Catch-In-Focus and the Pentax-F Autofocus adapter do work with this lens if the light is good enough and there is sufficient contrast in the target.

All in all a really nice piece of kit. Recommended.
Forum Member

Registered: November, 2014
Posts: 70

1 user found this helpful
Lens Review Date: July 28, 2015 I can recommend this lens: Yes | Price: $150.00 | Rating: 9 

Pros: sharpness, focus throw, super small, super light
Cons: none
Sharpness: 8    Aberrations: 9    Bokeh: 6    Handling: 9    Value: 10    Camera Used: K-3   

Spent several weeks reading mirror lens reviews on the net. Finally I decided for the Tamron because of its long focus throw.
Unlike other mirror lenses (Samyang et al), this one has a focus throw of almost 360°. Still, the DOF is so thin that every milimeter on the focus ring counts.

The key is to use a tripod, mirror lockup and be very accurate with focus, then this lens provides perfect results. My first 5 shots or so were bad, then I learned that I absolutely have to use a sturdy tripod, mirror lockup, 2 second timer and remote.
Also, with 500mm, air pollution and air movement suddenly becomes an issue.

If you're doing it right, this lens provides stunning images.

My guess is that the bad reputation of mirror teles is mostly due to people not being able to use them correctly. They handle like kit lenses, that's probably why noone bothers using a tripod and then blames the mirror construction for the bad results.

Site Supporter

Registered: August, 2011
Location: South Florida
Posts: 31
Lens Review Date: November 6, 2014 I can recommend this lens: Yes | Price: $200.00 | Rating: 10 

Pros: Very sharp for a mirror
Cons: None
Sharpness: 10    Aberrations: 9    Bokeh: 7    Handling: 9    Value: 10    Camera Used: K-3   

Great lens, great optics, great quality. I tried other mirror lenses and long teles and this one was light years ahead. The price was very reasonable which is good for a lens that has limited use. I put it through my usual lens tests and it performed surprisingly well, almost matching other Pentax telephotos. The colors are quite good too.
New Member

Registered: August, 2013
Posts: 11
Lens Review Date: February 14, 2014 I can recommend this lens: Yes | Price: $160.00 | Rating: 9 

Pros: Sharpness, compact
Cons: Needs sunlight
Sharpness: 9    Aberrations: 9    Bokeh: 7    Handling: 10    Value: 10   

What a great lens! A compact 500mm that provides great pictures with a really good IQ and sharpness. Turned into a 750mm with my Kr, it is really impressive how it can shoot far things.

The perfect condition is sunlight, a bright day so you can shoot at hogh shutter speed.

Taken at 1500m distance

Taken at 1200m distance
New Member

Registered: November, 2013
Location: Port Orchard, WA
Posts: 10
Lens Review Date: January 24, 2014 I can recommend this lens: Yes | Price: $100.00 | Rating: 8 

Pros: Massive zoom, Small for focus, Close focus, Crisp.
Cons: Donuts, Slow aperture.
Sharpness: 9    Aberrations: 8    Bokeh: 5    Handling: 10    Value: 9   

My copy of this lens was purchased used, but appeared near new when it arrived. I use it with a UV filter and the hood attached at all times. I don't think I would ever use the lens without the hood, as it seems a little too exposed. My lens did not come with the additional small filters and only had the normal small filter.

I have used this lens with both the K-3 and my former Canon 10D and 20D. Despite the issues that come with handling a lens like this (donuts, stabilization, and fixed superzoom), I absolutely love this lens. While it isn't especially versatile, I have such a fun time with this lens. The close focus ability makes pseudo macro shots with this lens easy. I got frustrated using this lens due to the f8 with my Canons, but I really enjoy using it with the K-3 as I have so much more ISO headroom. The internal stabilization really helps as well getting shots when it is cloudy or I am in the woods. This lens is easy to carry around, is not too large or heavy, and is reasonably easy to handle without a tripod or monopod. You will have better results with a monopod or tripod, but I have not found them to be 100% necessary--especially on sunny days. I would actually prefer to carry this lens to my 70-210 due to the weight of the 70-210.

Here are some samples:
Forum Member

Registered: September, 2013
Posts: 62
Lens Review Date: December 26, 2013 I can recommend this lens: Yes | Price: $150.00 | Rating: 9 

Pros: short, not expensive, fast enough
Cons: "macro" option is useless
Sharpness: 9    Aberrations: 10    Bokeh: 8    Handling: 9    Value: 9   

overall everything is good. hood included.
"rings" bokeh - known and not SO MUCH bad thing.
f/8 - fast enough for mirror lens, aberration... sharpness... but:
who the hell is really need this stupid "macro" range of focusing? Mirror lens at close range is nonsense!
this option is useless, and just affecting long distance focusing, at LR distances focusing ring travel is too short.

overall not bad at all. if You need 500 mm compact and cheep lens - try it, not a big-deal.
Site Supporter

Registered: April, 2011
Location: Lost in translation ...
Posts: 17,971

1 user found this helpful
Lens Review Date: December 21, 2013 I can recommend this lens: Yes | Price: $130.00 | Rating: 8 

Pros: Build, small-ish, focus throw ...
Cons: F8 and usual mirror issues, but I like "doghnut" bokeh ...
Sharpness: 8    Aberrations: 8    Bokeh: 8    Handling: 8    Value: 8   


Just acquired this 55BB with case, hood, cap & 01F 2x TC and like what I have seen thus far ... only a few outdoor test shots, since the outside weather is wet and cold ... will post samples later.

Giving a straight across "8" rating until more test and use can be done ...

Allez et salut, Jean le Green Frog

Here's some p0rn shots to see what the 55BB looks like on the K-5 ...

Senior Member

Registered: May, 2012
Location: Sunshine Coast
Posts: 113
Lens Review Date: July 3, 2012 I can recommend this lens: Yes | Price: $450.00 | Rating: 8 

Pros: Small and light for its focal length, beautifully made.
Cons: Fixed F8, manual focus.
Sharpness: 7    Aberrations: 10    Bokeh: 5    Handling: 8    Value: 9   

I bought this lens new back in 1983 for my ME Super, It was one of my favourite lenses, and I used it off and on until 2002 when I put my ME aside to do video and compact digital stuff. It was always kept in a hard case when not in use, so it still looks and works like new. Now I have my Kr I've bought it back out of use again. I still love it as much as ever. It is good to see a bit of a resurgence in interest in these lenses. They truly were and still are, fine pieces of optical engineering. I just wish I had also bought the 350mm version as well when I had the chance.
Veteran Member

Registered: November, 2009
Location: Strand
Posts: 1,366
Lens Review Date: March 6, 2012 I can recommend this lens: Yes | Price: $220.00 | Rating: 10 

Pros: Compact, light weight, sharp, minimum focus distance
Cons: Ring bokeh, little focus throw at near infinity
Sharpness: 10    Aberrations: 9    Bokeh: 7    Handling: 9    Value: 10   

Ring bokeh can be used in selected cases, not need to be negative.
Sharp overall. Very close focus distance to be a 500mm lens. Easy to focus within 20m/60feet, but harder at near infinity. SR very useful for hand held.
This lens is not for beginners.
Inactive Account

Registered: June, 2011
Location: Melbourne
Posts: 9
Lens Review Date: March 5, 2012 I can recommend this lens: Yes | Price: $200.00 | Rating: 8 

Pros: Lightweight, sharp, contrasty lens
Cons: unusual bokeh
Sharpness: 8    Aberrations: 9    Bokeh: 4    Handling: 8    Value: 7   

Generally it's a value lens if the price is below $200.

The best about this lens is sharpness with very little aberration and close to none vignetting. Similar to other mirror lenses, it's much lighter and more compact compare to conventional long range tele lenses. However it still needs steady support when shooting as it's not easy to focus with lenses with more than 300mm focal length.

The bad about this lens is it's donut-like bokeh that looks unusual. details in out of focused zones are almost lost. If your focusing is spot on, you'll have clear, sharp images out of the lens.

The macro function works well and this lens give you a closer focus distance when shoot in macro than many mirror lenses.

A protective filter is recommended for this lens as dust can easily fall on to the mirror.

Add Review of Tamron Adaptall-2 SP 500mm f/8 Mirror (55BB)

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