RF close-focus vs SLR lenses

[jett]

I'm entering the world of digital (sort of) with a Sony A7. I've never adapted "legacy" lenses on a camera before, so this is somewhat new to me.

I decided to start with a "regular" mechanical adapter (fotodiox pro for Leica M) because I hardly focus closer than 1m on 50mm or closer than 0.7mm on 35mm/40mm. I don't usually use any other focal lengths either.

What are the advantages of getting one of the close-focus adapters, as opposed to adapting SLR lenses? I figured that SLR lenses would generally perform better (especially at Macro levels) but at the expense of being larger and heavier.

 

[YYV_146]

I'm entering the world of digital (sort of) with a Sony A7. I've never adapted "legacy" lenses on a camera before so this is somewhat new to me.

I decided to start simple with a "regular" mechanical adapter (fotodiox pro for Leica M) because I hardly focus closer than 1m on 50mm or closer than 0.7mm on 35mm/40mm. I don't usually use any other focal lengths either.

What are the advantages of getting one of the close-focus adapters, as opposed to adapting SLR lenses? I figured that SLR lenses would generally perform better (especially at Macro levels) but at the expense of being larger and heavier.

For one thing, you can get extremely close on some lenses. the wider the lens, the more "macro" the adapter can achieve. At focal lengths below 24mm you are practically limited by things touching the front element, which makes for some very interesting effects.

For some lenses, it helps with tight composition. I didn't particularly like the 1m close focus on the 90mm APO cron when I had it. The adapter made close compositions.

 

[Kate-the-Great]

If you don't anticipate needing to focus closer than 0.7-1m, then RF lenses on a simple adapter are fine. I have occasionally found the 1m minimum distance on my Serenar 28mm and Industar-61 limiting on my X-E1 when shooting things like close-up portraits, but not enough so to invest in a close-focus adapter.

SLR lenses with floating elements (ie CRC) may have an advantage at close distances, but then again, some newer RF lenses also have CRC (a sidenote- using an RF lens that has floating elements on a close-focus adapter would probably be a bad idea). Other than that, optical performance of SLR vs RF lenses ought to be similar, perhaps with an edge to the RF lenses in the case of wides.

 

[Dwig]

...
SLR lenses with floating elements (ie CRC) may have an advantage at close distances, but then again, some newer RF lenses also have CRC (a sidenote- using an RF lens that has floating elements on a close-focus adapter would probably be a bad idea). ...

Anytime you add extension to make a lens with CRC (Nikon's term) type close focusing correction focus closer, you should first focus the lens to its minimum focusing distance and then use the extenison's adjustment ability (if it has one) to do any further focusing adjustment.

 

[ulrich.von.lich]

As far as I know, the adapter with close focus ability can be switched quickly between a regular adapter mode and a macro tube mode (without intoducing any extra glass element). The design seems quite smart, I don't know how convenient the actual use is.

Some "legacy" lenses can already focus down below 0.7m on a regular adapter, such as the 50mm Summicron DR and the Nikon 50mm f1.4 and f2 LTM lenses (to about 0.5m), and they are optimised for performance at close distances. I can only imagine the close focus adapter would allow them to focus even closer.

 

[kxl]

As already stated, at .7m to 1m, adapted RF lenses are more convenient, especially with a 50mm FL. If you use a 35mm, just note that not all adapter 35mm lenses work well with the A7. Center sharpness is fine, but edges and corners sometimes come out smeared -- this may or may not matter at such close distances with razor-thin DOF.

If you are truly talking about macro distance to produce images with life size (1:1) or greater than life size (2:1, 3:1, etc...) magnification, then this where an SLR macro lens or an SLR lens with extension tubes or a reversed SLR lens will shine.