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Pentax 645 35mm lens
- Thread starter felix5616
- Start date
I have extensively tested both on the 645 D and Z. In terms of flair, there are neglegable differences. In terms of color fringing, again no differences detected. Here are some of the differences I would note:
If you are a landscape shooter and shoot at f8 and especially more closed down, a relatively small difference can be detected at the edges of a flat field subject at great distances towards infinity. As pointed out, this is due to field curvature exhibited in the non HD version. This is accentuated if shooting at f4 and f5.6.
The field curvature lessens as the subject distance decreases from infinity.
I will say though that when shooting both certain types of landscapes that were not flat field and also park like settings that had objects at varying distances, the non HD rendered objects in foregeound at the sides and edges of frame better than HD version giving the image more of a 3D look and dimentionality. Not all landscapes are flat field at infinity..some are and some aren't.
Also the HD version in general exhibits equivalent sharpness up to approx. a stop earlier than the non HD. Again this can vary depending on subject matter and subject distance.
So my short answer is it depends what you are going to use the lens for. At close range on a flat field object, the non HD was sharper in the center of the frame and held its own across the frame from f4 and beyond but as distances grew larger, field curvature became more prominant in the non HD version.
I should note that these observations were done by examining files at 100%.
There is also sample variation in both versions and this can make quite a differences.
For full disclosure, I currently have a LN++ FA 35mm f3.5 645 lens for sale on this site.
Dave (D&A)
If you are a landscape shooter and shoot at f8 and especially more closed down, a relatively small difference can be detected at the edges of a flat field subject at great distances towards infinity. As pointed out, this is due to field curvature exhibited in the non HD version. This is accentuated if shooting at f4 and f5.6.
The field curvature lessens as the subject distance decreases from infinity.
I will say though that when shooting both certain types of landscapes that were not flat field and also park like settings that had objects at varying distances, the non HD rendered objects in foregeound at the sides and edges of frame better than HD version giving the image more of a 3D look and dimentionality. Not all landscapes are flat field at infinity..some are and some aren't.
Also the HD version in general exhibits equivalent sharpness up to approx. a stop earlier than the non HD. Again this can vary depending on subject matter and subject distance.
So my short answer is it depends what you are going to use the lens for. At close range on a flat field object, the non HD was sharper in the center of the frame and held its own across the frame from f4 and beyond but as distances grew larger, field curvature became more prominant in the non HD version.
I should note that these observations were done by examining files at 100%.
There is also sample variation in both versions and this can make quite a differences.
For full disclosure, I currently have a LN++ FA 35mm f3.5 645 lens for sale on this site.
Dave (D&A)
Last edited:
Shashin
Well-known member
I use the manual focus A 35mm on a 645D. It will flare when pointed into the sun. I have not noticed any field curvature for most street or landscape work. I am pleased with the sharpness. Is it better than the FA version? I have no idea, but I Purchased this version based on a Japanese review saying that corner sharpness was a tad better. I like the color rendering from this lens. Naturally, the AF is better in the FA version. But this is more compact.
I understand the 28-45mm zoom is better.
I understand the 28-45mm zoom is better.
The 28-45 is a very good lens. Some distortion but its manageable, exceptionally good central sharpness which falls off towards the sides and edges but sharpens up nicely when stopped down. As you probabaly already know..quite big and heavy, especially when mounted to the 645Z and this has discouraged some from taking/using it regulary, but well balanced on the D or Z
There are always trandeoffs regardless of the decision of which lens to cover the effective 28mm focal length on a 645 digital body and a case could be made for any of them?
Dave (D&A)
cornwallis
New member
Not exactly what you're asking but maybe it's of interest anyway - I've had three copies of the manual A version, and now I have the HD version. I'm using it with a Cambo Actus and Sony A7r.
The HD version is slightly sharper in the centre (which is to say very sharp indeed, as good at my 24mm tse), and when focused precisely it holds its sharpness into the corners much better than the A version. When I say corners I mean, roughly, of a 6x4.5cm film area (I'm stitching). Maybe on a 645z size sensor the difference wouldn't be so clear. CA is much improved. Flare is improved, though sunstars etc. are much more appealing in the older A lens for some reason.
The HD version has similar complex distortion to the A version, but it is less severe. For a 645z size stitch, the distortion on the HD version is quite easy to correct, I found the A was harder in this regard.
But... field curvature seems significantly worse on the HD version, at least at the distances I tend to shoot at (I'm often focused a little short of infinity). I nearly gave this lens back as I found the edge performance much worse than the A (shooting at f8 or 11), until I learned to focus fractionally deeper into the scene than felt natural. Once I did that I was very impressed with the sharpness from centre to corner. Will be tricky on some subjects though.
I was going to try the FA version against the A, but I had a rush of blood to the head and jumped straight to the HD one... I would imagine the two (or three?) AF flavours of this lens are much closer to each other then they are to the original A.
The HD version is slightly sharper in the centre (which is to say very sharp indeed, as good at my 24mm tse), and when focused precisely it holds its sharpness into the corners much better than the A version. When I say corners I mean, roughly, of a 6x4.5cm film area (I'm stitching). Maybe on a 645z size sensor the difference wouldn't be so clear. CA is much improved. Flare is improved, though sunstars etc. are much more appealing in the older A lens for some reason.
The HD version has similar complex distortion to the A version, but it is less severe. For a 645z size stitch, the distortion on the HD version is quite easy to correct, I found the A was harder in this regard.
But... field curvature seems significantly worse on the HD version, at least at the distances I tend to shoot at (I'm often focused a little short of infinity). I nearly gave this lens back as I found the edge performance much worse than the A (shooting at f8 or 11), until I learned to focus fractionally deeper into the scene than felt natural. Once I did that I was very impressed with the sharpness from centre to corner. Will be tricky on some subjects though.
I was going to try the FA version against the A, but I had a rush of blood to the head and jumped straight to the HD one... I would imagine the two (or three?) AF flavours of this lens are much closer to each other then they are to the original A.