[nugget247]

This is quite accurate: including the k-mount adapter, it measures to pretty much exactly 12cm, at 160mm and infinity focus.



Indeed! Using this number (10.5cm) with the Wikipedia formula for magnification at closest working distance, one gets almost exactly the magnifications I am seeing at MFD with the DCR-250 (1.5:1) and the MSN-202 (2.9:1). There's the issue of why the actual working distance is measured to be significantly greater than 10.5cm, but your idea of X = MFD-L-F where MFD is the minimum focus distance, L is the length of the lens at infinity focus and F is the flange distance does seem plausible. However, it's odd that it works so well in that the lens extends quite significantly at MFD and then measures more like 14.5cm. It would be interesting to test a couple of other lenses to see if the formula (with your definition of X) works for them too...

Based on the formulas, the 52B with 01F combo should be able to cover from about .8x to 2.1x with only the DCR-150. That would be a very convenient range for an equivalent 180mm lens. The Canon 250D and Olympus MCON-35 close up lenses are +4 and +2.8 diopter respectively and both at least equal the optical quality of Raynox from everything I have read. These two would give theoretical magnification ranges of .7x to 1.9x and .5x to 1.6x respectively. These are all great ranges, and I will probably go with this lens combo and whichever of the close up lenses comes my way 2nd hand for a good price first. Hopefully it's a Raynox so I can appropriately share some images here

[WPRESTO]

For comparison, the first shot is with a 200mm SMCA with a Raynox 1.5X, the secondimage is a crop from the same file. Then a photo of the rig. Next image is the same penny with the 200mm SMCA with a reverse mounted 100mm SMCA bellows, and last a crop from that image file. To no one's surprise posting on this thread, the Raynox delivers excellent IQ, but not to the quality of the reversed bellows lens, although to be fair, the cropping is obviously less severe than with the R1.5X. Also, the uncropped image with the Raynox appears to drift from sharp on the lower margin to soft at the top, so the penny may not have been exactly perpendicular to the line of site. BTW: These are two of a long series of tests that included a fine macro (Tokina 90mm f2,5) that delivered IQ @ 1:1 that was at best only marginally better than the Raynox, but maybe not.

[hoopsontoast]

Mixture of K85 and F70-210 with the DCR-250

[AggieDad]

For comparison, the first shot is with a 200mm SMCA with a Raynox 1.5X, the secondimage is a crop from the same file. Then a photo of the rig. Next image is the same penny with the 200mm SMCA with a reverse mounted 100mm SMCA bellows, and last a crop from that image file. To no one's surprise posting on this thread, the Raynox delivers excellent IQ, but not to the quality of the reversed bellows lens, although to b e fair, the cropping is obviously less severe than with the R1.5X. Also, the uncropped image with the Raynox appears to drift from sharp on the lower margin to sift at the top, so the penny may not have been exactly perpendicular to the line of site. BTW: These are two of a long series of tests that included a fine macro (Tokina 90mm f2,5) that delivered IQ @ 1:1 that was at best only marginally better than the Raynox, but maybe not.

Considering the almost nominal difference in the IQ - especially compared to the ease of use compared to reversing the lens and adding the bellows - I think you just convinced me that a Raynox is the way for me to go.

Thanks for the comparison shots.

[schnitzer79]

a few from the other day (with the DCR-150)
B&W ones are with the Helios 44-2 58mm f/2 and the others with the Carl Zeiss Flektogon 35mm f/2.4. I love my M42's

[WPRESTO]

The first snail shot is an eye-grabber. personally, I would crop it to a near-square as there is non-contributing material on both sides.

[schnitzer79]

The first snail shot is an eye-grabber. personally, I would crop it to a near-square as there is non-contributing material on both sides.

thanks for the tip. ill give it a try and see how it looks

[ToyTank]

For comparison, the first shot is with a 200mm SMCA with a Raynox 1.5X, the secondimage is a crop from the same file. Then a photo of the rig. Next image is the same penny with the 200mm SMCA with a reverse mounted 100mm SMCA bellows, and last a crop from that image file. To no one's surprise posting on this thread, the Raynox delivers excellent IQ, but not to the quality of the reversed bellows lens, although to be fair, the cropping is obviously less severe than with the R1.5X. Also, the uncropped image with the Raynox appears to drift from sharp on the lower margin to soft at the top, so the penny may not have been exactly perpendicular to the line of site. BTW: These are two of a long series of tests that included a fine macro (Tokina 90mm f2,5) that delivered IQ @ 1:1 that was at best only marginally better than the Raynox, but maybe not.

Thank you for the comparisons!

[WPRESTO]

Because there was interest in the previous post from the long series of macro tests I made, here is another. The lens is a SIgma 18-250 set at 250mm and infinity focus with a Raynox 1.5X lens, an uncropped image and a crop of the "UM" from "UNUM." For all tests in which a diaphragm equipped lens was attached to the camera, the lens was set @ f8 and the strobe adjusted to get the light as close as possible to the same exposure. The only PP done was tweaking the exposure. Some zooms vignetted severely with the Raynox, notably the 17-70mm Sigma at all focal lengths and distance settings. However, @70mm, closest focus distance, R1.5X attached, the vignetting can be eliminated by cropping leaving an image that included slightly more than the entire penny (estimated 1:1.5 ratio) that was tack sharp with excellent detail in the corrosion around "UM." Also FYI: The Raynox generally gave results at least as good or better than either Nikon 2T, 4T lenses, or Canon 250D, 500D lenses, although the latter can be fitted to lenses where the Raynox cannot (example: 60-250 Pentax).

[Thomas Cantwell]

Can anybody please tell me what the max magnification and what infinity focus looks like for both the raynox dcr250 and 150, combined with the 77 1.8?

[mtux]

Can anybody please tell me what the max magnification and what infinity focus looks like for both the raynox dcr250 and 150, combined with the 77 1.8?

Here calculate it yourself.
dcr-150 has a diopter of 4.8 and 250 has diopter of 8.

[hoopsontoast]

K85 / DCR-250

[Thomas Cantwell]

Here calculate it yourself.
dcr-150 has a diopter of 4.8 and 250 has diopter of 8.

Thanks! 250 gives .84x mag and 150 gives .56x. I'm still curious about The maximum focusing distance, though.

[audiobomber]

Thanks! 250 gives .84x mag and 150 gives .56x. I'm still curious about The maximum focusing distance, though.

This is an interesting calculator, specific to Raynox diopters:

• A 77mm and Raynox 250 combination "gives you a 0.84:1 macro lens, with a working distance of between 10.61 cm and 12.5 cm depending on your focus"

Using Raynox Adapters For Extreme Macro

The above is a great site for all things macro. The author, Johan J. Ingles, is a moderator here at Pentax Forums (screen name Nass): Extreme Macro Photography

[mtux]

Thanks! 250 gives .84x mag and 150 gives .56x. I'm still curious about The maximum focusing distance, though.

As mentioned in Raynox's website, the working distance (when focus is set to infinity) with 150 is 20cm and with 250 is 10cm! and as you change the focus to MFD the working distance will be shorter a bit, probably around 1 to 2 cm as audiobomber mentioned.