[miltllama]

I tried googling this, but didn't really find anything other than comparisons between macro and close-up lenses. My question is, can you use a close-up lens with a macro lens to get greater than 1:1 shots? For reference, I have the DFA 50, so I'm thinking along the lines of the Canon 250D.

[edgedemon]

I can't answer yor questions, but I know there was a guy on flickr who was getting some amazing close up shots using an old manual 50mm prime that he had reversed using a reversing ring and added some extension tubes..

[Ash]

By closeup lenses, do you mean those cheap 'close-focus filters'?
If so, they're not all that popular for reasons of image quality: https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/98692-close-up...mron-90mm.html, https://www.pentaxforums.com/forums/pentax-beginners-corner-q/69815-close-up-filter.html, https://www.pentaxforums.com/forums/pentax-camera-field-accessories/45280-clo...ood-macro.html

If you're talking of reversing a lens piggybacked onto your DFA 50, you can indeed get very closeup results of good quality. Or you can use extension tubes with a reversed 28mm/50mm prime lens on the end that can give you some extreme macro results - these have very shallow depth of field, though. Focus stacking is generally a good idea in these situations.

[jolepp]

With a 50mm lens using a close-up add-on is probably impractical as you'd need > +20 diopter one. Using extension tubes should get you beyond 1:1 cheaply and with good image quality. The basic $10 ebay tube set works fine for me :-)

[miltllama]

I've really only heard of those Canon ones, I don't know too much about them, I was just curious. I did see lens-stacking rings on B&H for not too much, but how does metering work through a second lens? Would I still be able to use small apertures for more DOF?

[RioRico]

Among the most popular corrected close-up strap-ons, much better than cheap +dioptre sets, are the Raynox DCR-250 and -150, similar to the Canon you mentioned. With such, you maintain complete lens automation, which you would lose with cheapest macro tubes. This is mostly important if you intend to use flash. Or you can buy tubes with aperture linkage (which are a bit rare) or the old workaround: auto-aperture-link TC's with the glass removed. Remember that no matter how much extension (tubes and/or bellows) you use, a non-reversed lens cannot focus closer than its focal length. Longer lenses allow/force you to work further back.

You can get great magnification with lens-stacking using a thread-reversal ring. Your PRIMARY lens is mounted on the camera; a reversal ring is threaded onto its front; then your SECONDARY lens screws onto that. Magnification is the ratio of focal lengths, PRIMARY:SECONDARY. So a 50mm primary stacked with a 25mm secondary gives 2:1 or 2X magnification.

TANSTAAFL (no free lunch) - Limitations: With any reversed lens, your working distance is very close, under two inches. The primary lens aperture must be wide open or your image will be vignetted. Control light and DOF with the secondary lens aperture, which must be manual -- gotta have an aperture ring!

how does metering work through a second lens? Would I still be able to use small apertures for more DOF?

Plain ordinary thru-the-lens metering: point and meter. With a Raynox or Canon or +dioptre add-on, light isn't diminished much. With extension or a stacked lens, light IS reduced, which is why we use flash or studio lights or a tripod. Yes, shrink the aperture for more DOF -- but DOF is painfully thin at macro distances. Soe resort to focus-stacking: take shot with slightly different focus, then combine them in PP.

[newarts]

The $50 Raynox DCR 250 (125mm focal length) is about twice as strong as the canon 250D (250mm).

On the FA 28-70/4 it would give magnifications of up to about 0.85X; The canon 250D or Raynox DCR 150 would give magnifications up to about .5X while maintaining all automatic functions.

[miltllama]

Magnification is the ratio of focal lengths, PRIMARY:SECONDARY. So a 50mm primary stacked with a 25mm secondary gives 2:1 or 2X magnification.

Thanks for your excellent response! But, does this mean that if I stacked my A50 onto my DFA50, the magnification would remain 1:1?

[jolepp]

Thanks for your excellent response! But, does this mean that if I stacked my A50 onto my DFA50, the magnification would remain 1:1?

Yep, and you'd get lower IQ and <2" working distance too.

[RBellavance]

One point that has not been made yet is that all a close-up filter gives you is closer focus (in fact, they give you a *fixed* focus distance). If that distance is not closer than the "native" one of the macro lens, you gain nothing and lose IQ in the process.

[newarts]

One point that has not been made yet is that all a close-up filter gives you is closer focus (in fact, they give you a *fixed* focus distance). If that distance is not closer than the "native" one of the macro lens, you gain nothing and lose IQ in the process.

Granted image quality likely doesn' t increase using a Raynox or equivalent quality closeup lens but it is still excellent in the many cases reported here in the " Raynox Club" thread.

The reason I suggested using a good close-up lens on the poster's zoom lens is that a range of magnifications will be covered by zooming. From about 0.22x to about 0.8x with the Raynox 250. Maximum working distance would be about 125mm for the Raynox 250, compared to 45mm for a reversed 50 mm lens.

The closest focusing distance using a close-up lens attachment is always smaller than without it.

[RioRico]

But, does this mean that if I stacked my A50 onto my DFA50, the magnification would remain 1:1?

The magnification calculation is based on both primary and secondary lenses being at infinity focus -- that is, with minimum extension. If you focus the primary closer, which is the same as adding extension to it, magnification increases. I'll refer to the bible of macro+technical work, FIELD PHOTOGRAPHY by Alfred A. Blaker (still available cheap at Amazon -- BUY ONE NOW!!): With a 35mm secondary stacked on a 105mm primary, MAG= 3:1. If you add 26mm extension to the primary, MAG= 4:1. Blaker doesn't give the math on that, but he says it's so, and I Want To Believe...

Also in that calculation, the lenses' front insets aren't considered. I'm not sure how greater separation of the pobjectives affects magnification. Deep insets will cause on stacked lenses will cause vignetting. A deeply inset manual lens gains magnification just by flipping it with a mount-reversal ring, because the inset effectively adds extension, but you're still down to that 45mm working distance.

Anyway, whilst you await the arrival of the thread-reversal ring(s) you've ordered, there's an easy way to experiment with this stuff. Use gaffer's tape (NOT nasty residue-leaving duct tape) to stack lenses. That's an old field-shooter's trick. Put your lenses face-to-face and tape tightly. Another trick: Screw a mount-reversal ring into the front of a standard (non-macro) manual prime with deep front inset. Wander around with the lens mounted normally, shooting whatever catches your eye. To shoot macro, just flip the lens! And close to 45mm from your subject...

[miltllama]

One point that has not been made yet is that all a close-up filter gives you is closer focus (in fact, they give you a *fixed* focus distance). If that distance is not closer than the "native" one of the macro lens, you gain nothing and lose IQ in the process.

Thanks for clearing this up, I wasn't quite understanding how they worked. My initial assumption was that they were essentially a "magnifying glass", so they'd just increase the magnification of a macro lens, but it totally makes sense that they'd just allow you to focus closer with normal lenses, which is why they're a good cheaper alternative to dedicated macro's if you don't want to spend the money, but since I already have one, it's pretty pointless.

[miltllama]

The magnification calculation is based on both primary and secondary lenses being at infinity focus -- that is, with minimum extension. If you focus the primary closer, which is the same as adding extension to it, magnification increases. I'll refer to the bible of macro+technical work, FIELD PHOTOGRAPHY by Alfred A. Blaker (still available cheap at Amazon -- BUY ONE NOW!!): With a 35mm secondary stacked on a 105mm primary, MAG= 3:1. If you add 26mm extension to the primary, MAG= 4:1. Blaker doesn't give the math on that, but he says it's so, and I Want To Believe...

Also in that calculation, the lenses' front insets aren't considered. I'm not sure how greater separation of the pobjectives affects magnification. Deep insets will cause on stacked lenses will cause vignetting. A deeply inset manual lens gains magnification just by flipping it with a mount-reversal ring, because the inset effectively adds extension, but you're still down to that 45mm working distance.

Anyway, whilst you await the arrival of the thread-reversal ring(s) you've ordered, there's an easy way to experiment with this stuff. Use gaffer's tape (NOT nasty residue-leaving duct tape) to stack lenses. That's an old field-shooter's trick. Put your lenses face-to-face and tape tightly. Another trick: Screw a mount-reversal ring into the front of a standard (non-macro) manual prime with deep front inset. Wander around with the lens mounted normally, shooting whatever catches your eye. To shoot macro, just flip the lens! And close to 45mm from your subject...

Wow, that kind of math would make my head hurt, I'll just take the author's word for it! I think I'll try using gaff tape (fortunately I have a ready supply from my workplace), just to try a new technique, but it's sounding like the best option for greater than 1:1 would be extension tubes with my macro lens. Unless that won't work either?!

[yeatzee]

I can't answer yor questions, but I know there was a guy on flickr who was getting some amazing close up shots using an old manual 50mm prime that he had reversed using a reversing ring and added some extension tubes..

Im assuming: Flickr: Thomas Shahan's Photostream