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Pentax 28-70 mm f4 AL on Sony a6500

Continuing in my quest to find a decent general purpose zoom  to use with my Sony a6500 camera, I've just taken delivery of a used Pentax 28-70 mm f4 AL lens. This is a light and compact lens. In common with other early autofocus lenses from Pentax the focusing ring is a bit loose and vague, but it's not diffcult to achieve accurate manual focus. Working at f8, my initial impressions are reasonably favourable. From 50 to 70 mm it appears very sharp across the frame. Below that the edges fall away a bit, with 28mm being the weakest focal length, but central definition remains good throughout. I have a feeling that this may be due to a field curvature issue, as better results are obtained by focusing near the edge of the frame rather than in the centre. I need to do more testing and use the lens for some practical photography, but this one may well be a keeper! Further testing has confirmed my fear that. at 28mm, the edges are very soft. A pity because at the centre at 28
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Pentax A 28-80 f3.5 - 4.5 lens on Sony a6500

I'm continuing to search for a half decent walk around lens for my Sony a6500, having tried and discarded the Zeiss and Sony offerings. My latest discovery is a Pentax A 28-80 f3.5-4.5 zoom from the film era. I've had my copy for years, bought second hand it's not in the best of condition, with marks visible on the front element and a general slackness in the zoom helicoid. This is what it looks like on the camera. Be warned, this is a manual focus lens, if that's not your cup of tea, read no further! It's no lightweight being of mixed metal and plastic construction. With adapter it weighs 502 g, but this is appreciably lighter than the Tamron 28-80 that I have also tested. How does it perform, I've not conducted any brick wall tripod tests as yet, but having taken a number of shots with it I am reasonably impressed.  Here's an example. It was a muggy, hazy day with poor visibility, but the image quality is OK First of all the overall

Minolta Rokkor Enlarger lens on Sony a6500

I've been experimenting with my old enlarger lenses as a means of scanning old negatives and slides, but, out of curiosity, decided to see if they could be used as prime lenses for distance work on the Sony a6500. The lens in question is a Minolta Rokkor 75 mm f4.5. In order to do this you need to buy a focusing helicoid as enlarger lenses relied upon a bellows or helicoid within the enlarger to focus the negatives. You also need an M39 to M42 adapter as enlarger lenses came with the old Leica thread that is, nowadays, non standard. Finally an M42 to Sony E fit adapter completes the kit. Enough of the cackle, how does it do? Very well actually, here's a view from the rear of our house and an actual pixels crop from the extreme left of the frame. Click for larger images. The image is sharp to the edge of the frame with no sign of any CA - possibly helped by the fact that I have CA removal permanently engaged in Lightroom! It's an unfair comparison I k

Tamron Adaptall SP 28-80 f3.5- f4.2 on Sony A6500

I'm continuing to search for a suitable walk around zoom for use with the Sony a6500, having tried and rejected both the Zeiss 16-70 and the Sony 28-70 .  It occurred to me that I had some old film era zooms lurking in the cupboard, and the most promising of the collection appeared to be the Tamron SP 28-80. If you are not familiar with Tamron Adaptall lenses, they were supplied with a range of adapters to suit the most popular makes of film camera. I possess a small collection of the these removable mounts, including M42, Pentax K, Olympus and Canon FD. The first mount I tried was the M42, it was nice and secure, but, in use, I quickly realised that I was unable to focus at a focal length of 28 mm - circa 30 mm and beyond were fine. Next came the Pentax, and that was better, but not perfect. Finally the Olympus, and that was much better, but the closest I can focus at 28 mm is about 1 m. Here is what the lens looks like mounted on the camera, click for a bigger image.

Using an enlarger lens and a Sony a6500 to copy negatives

This is very much a work in progress. I've assembled a collection of components and examined the feasibility, but not done any proper testing. Hopefully you will find it interesting. I have a large collection of negatives and transparencies dating back to the early 1960s, and I have scanned quite a number of them using an Epson 4990 Photo flatbed scanner. The results are OK, particularly for 120 film, but not so great for 35 mm. Sadly the film related section of the scanner failed recently, possibly due to overwork or maybe just old age, so I was interested in finding an alternative. If you have a good macro lens read no further, but if, like me, you don't possess a macro lens, then what is the next best thing? Well possibly an old enlarger lens. They were designed to provide the best possible resolution over a flat surface ( the negative) and project onto another flat surface (photo paper), both at close quarters, so, theoretically, they should be well suited to scanning.

Sony 28-70 FF lens on a6500

Since my kit 16-50 lens failed and was pronounced unrepairable I've been looking for a replacement walk around zoom, or, in my case, a lightweight lens that I can carry when cycling. I tried the Zeiss 16-70, but as my previous post here demonstrated, that lens was fatally flawed - as well as being expensive. I was persuaded to try the much cheaper 28-70 lens (cost £234 new) that is supplied as part of the standard kit on Sony full frame cameras. Let's give it its full title, the  Sony SEL2870 E Mount - Full Frame 28-70 mm F3.5-5.6 There are things to admire about this lens. It's compact and lightweight and handles well on the a6500. Despite being of plastic construction, it does appear well made, with a metal mount and a robust feel to it. I liked using it. Mounted on a tripod and shooting test pictures against a brick wall the lens is OK, nothing like as sharp at the edges as in the centre, but usable. Here are a few crops from a test shot at 28 mm and f8.  The upper

Sony Zeiss 16-70 f4

Wanting to cut down on the number of lenses that I cart around, and having suffered the failure of my Sony 16-50 zoom, I decided to try the top of the (crop format) range Zeiss badged Sony 16-70 f4. This is not a cheap lens, I paid £605 but with a potential cashback from Sony. First the good news. It appears very well constructed, and is relatively small and light given the specification. The focus is very fast and accurate coupled with the Sony a6500 body, and the centre of the images produced is biting sharp.  The colour produced is pleasantly neutral, the photos look good. The not so good news. The edge performance is variable, I would say barely adequate to poor. The lenses I hoped to replace with this Zeiss included a Sigma 19mm f2.8 ( cost £100) and an ancient Pentax 28mm f2.8 M from film days - the copy used here cost me £25. These two optics are the weakest amongst those that I regularly use. So to the comparison. All tests using a tripod with a 2 sec delay and at f8. I h