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STAY WELL AWAY. POOR QUALITY and DOESNT work on Wide angle Pentax 645 lenses.

Sooo, I finally bought this after coming across it on a few blogs (here included) and just wanted to post this quick update so that other people don't waste their money.

Upon receiving the adaptor I immediately went about buying a bunch of 645 lenses and was pretty excited by the promise of this adaptor for my A7Rii. HOWEVER, the quality of the optics is pretty poor and as someone mentioned there's a lot of smearing towards the sides of the image.

Then things got worse. When trying to attach my Pentax 645 45mm lens to it I found that it wouldn't even connect to the adaptor. After a lengthy email exchange with the supplier they finally admitted that it DOESN'T ACTUALLY WORK with wide angle Pentax lenses!!!!!!

Guess that might have been a useful thing to have known. 

Anyway, now I'm stuck with trying to get my money back. 

As the saying goes...'if it looks too good to be true'........

25 minutes ago, Nikkor said:

The Pentax 645d has a bigger cropfactor than this speedbooster. Even the most expensive backs are not really fullframe 54mm vs 56 

cool! I'd always just assumed that the digital 645 had the same FOV as film.

Thanks for clearing that up.

Weird, but guess that's a whole other topic

39 minutes ago, tweak said:

Not buying it for this reason would be the silliest thing I've read in a while. Most speed boosters don't boost back 100% to the optics original image circle, all are just shy of it usually.

I can't believe it's the silliest. Have you opened a newspaper and read anything coming out of the Whitehouse recently?

Anyhoo,

I'm not particuarly techy when it comes down to adapters but when my main reason for buying an adapter is because the manufacturer states that I can "Get the same view like on medium format cameras" with it then having a sizeable crop is going to be a deal breaker for me.

Guess a 645d is going to be the cheapest entry into digital MF for now. Shame.

3 hours ago, Mattias Burling said:

IMO, Wider field of view, sure it has a bigger sensor. But sharper..

Dont get me wrong, I love film and if I ever had to choose between them to use for the rest of my life it would be film.

And even though T-Max has a crazy amount of sharpness it cant be as sharp as digital in this experiment. Mainly because the scanner isnt very sharp. And on my screen it shows up that way.

Thanks for putting these tests up. It's a big help. I'd been looking at these a little while ago and after seeing your posts this week, had been tempted to pull the trigger on one in the next day or two.

However.....Looking at your last post you say that: "IMO, Wider field of view, sure it has a bigger sensor.". Do you mean that the field of view is smaller on the Sony?? Because on the official web site for the adaptor it states: "Get rid of crop factor. Get the same view like on medium format cameras".

When I looked at your last shots, it certainly looked like there was a pretty big crop factor but I thought maybe you'd just repositioned yourself BUT if there is a large crop factor it totally contradicts what they're saying on their website. Which is pretty disgraceful.

Be good to know what your thoughts on crop factor / field of view are.

Either way thanks for doing these tests. Might just have saved me wasting €500.