Reverse lens for macro photography

Hi guys, I've recently bought a K-x with kit lens and want to get into portrait and macro photography.

I've bought a Pentax-M 50mm 1.7 which I understand should be perfectly suited for portraits. However for macro work I believe I need to use a reverse lens mount for this. Can someone please advise or point me to a link where I can purchase this item and any tricks/techniques I should be aware of?

When I started looking for a suitable portrait lens, some people mentioned I should go for 80mm and some said 135mm while others say 50mm with macro - I dont understand how the requirements for portrait lenses could vary so much and would appreciate if someone could elaborate.

Thanks for your help
Mumin

Macro: 50mm general purpose lenses do not have flat fields like macro lenses do, but the f1.7 was the right choice for this as it is much better than the f1.4 up close. Performance can be vastly improved by reversing the lens and a reverse adapter K in 49mm size is required. SRB Griturn will have these, and probably lots of other suppliers as well. A 28mm lens reversed will give huge magnification.

Portraits: It depends on how close you want to be, but the classic film lens was the 85mm. The equivalent for digital is the DA 55mm f1.4 and I think the confusion arises here in that many photographers still get confused over focal length.

Personal choice also come into it and I always preferred the slightly longer 100mm on film. This means that my first choice would be the 70mm f2.4 which is the digital equivalent.

While you mull it over, you have a 55mm lens at the long end of your kit zoom, so see if this falls naturally as the portrait lens. If it does, then go for the 55mm f1.4 and you will enjoy wider apertures that can throw the background out of focus more easily. If you itch for something longer then you'll need to think of the 70mm or the 77mm.

Would suggest you type "reversing ring" into google for a mass of detailed information (far more than you're likely to get in a relatively short thread).

The basis is that you need a ring which has two male threads which fit into the filter threads of the two lenses you opt to use, so you will need to look for, for example 52/49mm; 52/52mm; 52/55mm, depending on the lens combinations (there are also itens such as step up and step down rings, which have a male/female of different sizes, that when used in combination with a reversing ring (of the wrong initial match) would help)
Ebay is possibly your best source for all of the above (you can generally ignor references to Canon/Nikon in this instance as you're only interested in the filter thread sizes)

I personally find I get vignetting using this mode, unless I fit a longer lens near the camera and a shorter lens outboard, so have yet to be satisfied with the results.

It was felt (and probably still is) that an optimum length for a portrait lens on a 35mm film camera was about 90-100mm.
On digital, allowing for a reduced sensor size, this equates to circa 60-70mm focal length (see other threads for discussions/arguments on digital/film focal lengths).

Much depends on the style of portrait that you want to do. If we momentarily flit over to bird photography you'll find some will have taken a birds "portrait" with maybe a 500mm lens, others have used 50mm. Neither is wrong, per say, but different.
I've started taking pics (yet to be defined as portraits) of my grand children. Some are using 35mm or less, because I can't get far enough away from them. Outside I often use a short telephoto because I don't want to intrude.


regards
Bernard

Edit,
In the time it took me to type my post, one of the site experts has provided you with a better answer -B

Can I just clarify that Bernard and muself are talking about two different things here.

I was discussing using a reversed lens on its own. Bernard is discussing revesing a lens onto another lens.

A book on macro photography could be in order to clarify all the techniques. It's far too much to cover in a forum thread.

Yes agreed, I had intended to go into that part but got sidetracked and ultimately I forgot all about that aspect.
And as you say the subject is vast.

regards
Bernard

Thanks to both of you - I feel I've learnt a lot in such a short space of time!

Yes - when I use the kit lens I am happy with the image when zoomed at 55mm, so the 55m prime should be ok for time being until I need more zoom. Also I am after the bokeh effect which my current kit doesnt provide.

Regarding the reverse lens options, at this moment I simply want to reverse the 55mm lens onto the mount and not onto another lens. So looks like I need a 49mm/52mm converter.

Thanks guys
Mumin

Have a look at (Premier Ink & Photographic), web site, for lens adaptor, reversing rings etc.
Good prices, plus very good service.

Disclaimer, I have no connection to, Premier Ink.


Sorry don’t know how to do the “link” to site thing.

Take care.

link

Hope that worked or I will look a fool

cool, will check the site out after work,

the link works by the way

I'm not so sure about that.
To reverse the lens to fit directly to the camera you will need a K mount on one side and your filter size (eg 55mm) on the other.

49/52 would be used to reverse a lens in front of a camera mounted lens

Following photo shows both. To reverse the lens onto the camera you need the bottom one

[IMG]http://i1236.photobucket.com/albums/ff444/Frogherder/IMGP0218-1.jpg[/IMG]

regards
Bernard

Incidentally
No one has mentioned yet that the lens needs to have a manual aperture adjustment. The M50/1.7 provides this and for that matter manual focus but you will lose all the automatic facilities that your camera provides. Metering, whilst (at least on my cameras) works moderately well, it's not quite as accurate as I'd like. Take a test shot first and adjust shutter/ISO accordingly


Regards
Bernard

As you have just bought an M50/1.7 for your macro work why not try it (the right way round) for portrait work to see if the focal length is what you would like? The DA 55 f/1.4 is an expensive lens and to be frank, the half stop and five mm difference isn't going to be hugely different, although the lack of AF will be. I'm assuming the IQ will be better on the DA but that is only an assumption. For a few test runs the M50 will at least give you a good feel for using a fast prime.

K.

great, thanks for the pic - this is exactly what I need - will look for it tonight

@womble - indeed I will, the main purpose is for portrait work but I fancied using it for macros as well.

The focus for me in my newbie stage is to keep costs right down - I can get dedicated macro lenses and 80/85mm primes later on but I am not prepared to splash out wads of money right now. Hence going for cheaper manual lenses and reversing connectors.

Appreciate the help guys!

There are a few genuine 49mm reverse adapters on ebay.
The engineering on these is really superb and an exact
fit on the camera body. You would also need a 49 -> 52mm
step up ring (or is it step down? )

link

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