Some sacrifices are worth making.

Steve

Getting your eye in before trying to snap NASA's next lunar mission as it passes the moon?

Steve

Or you can attach the 1.7x to the camera, then the 1.4x, and finally the Irix 150mm to give a 357mm f7.1 macro. It works - even the AF. Here's the proof of principle. 30cm from front of lens to eye, the white of the eye is 6mm diameter. Please don't try to judge the IQ of the stacked TCs from this image. The camera was on a tripod with wireless trigger and 3 sec delay but the tripod was on a carpet and I know from other shots that some vibrational blur can sometimes be seen.

One thing is clear, though - the DOF is very, very thin. Anyone care to try it handheld ?




Are you still wanting to sell the 1.7x, Mike-P ?

Steve

Interesting to see both photos in the same thread. Putting them both big and flipping between them, I can't honestly say that either is better than the other. Instead, they each have a different 'feel'. The sharper, mono one (second) one feels as if the moon is so close you can almost touch it. The softer, subtly coloured one (first) feels as if the moon is far away in the distance. Possibly due to the way we judge terrestrial distances from how objects appear.

So thanks to both for posting, It's made me think and that's a good thing .

Steve

Lovely bird, lovely photo. Almost as if it was posing just for you .

Knowing nothing about kookaburras myself, are they tricky things to photograph that disappear at the slightest hint of a human or are they like robins in my part of the world, quite happy to get close to a human on the grounds that where there's a human there might be food?

Steve

One question is left unanswered - did the lens actually take a trip to Germany in the end? If so, it seems from the timeline that the Germans were pretty efficient.

Steve

Could you put straight from camera image files with all EXIF data intact somewhere where we can download it? Preferably both RAW and JPG of the same picture. Someone might be able to spot something in the EXIF data which points to the cause of the problem.

Are you absolutely sure that the white balance settings are correct? I've occasionally found myself unintentionally changing white balance instead of something else because I pressed the wrong button initially then continued with a couple of presses through habit/muscle memory before looking at the rear screen.

And if it turns out that there really is a problem with the camera and it's not due to a rogue setting, is it possible to correct the magenta cast by adjusting the camera's white balance settings?

Steve

Just checked the lens and 1.7x and remembered why they don't attach. The reason is in a new thread in the 'Lenses for Pentax cameras' section in case it's useful to anyone. In a nutshell, Irix didn't bother with ensuring compatibility with equipment that pre-dated the 'crippled K-mount' (introduced with later film cameras). Pity.

Steve

A thread in the classifieds link notes that the Pentax 1.7x AF adapter won't mount on the Irix 150mm macro (this is the reason why the adapter is for sale). I had found the same thing but couldn't remember why. I've now checked the lens and adapter, so here is the reason why the adapter won't attach to the Irix.

The current K-mount on a lens has a long slot running along part of the inner edge of the mount face. It is needed to accommodate a tab (stop down coupler) on whatever is to be attached to the lens (camera, tube etc.). The Irix does not have that slot. The 1.7 AF adapter does have the tab. The lack of a slot prevents the adapter attaching to the lens. The tab does not protrude very far into the slot so the adapter almost attaches to the Irix, but 'almost' is enough to stop the bayonet from engaging. I confirmed it with an old set of extension tubes. A tube with the tab does not attach to the Irix, a tube without the tab (removed for another reason) does attach.

What is somewhat annoying is that the slot is only needed for back-compatibility with cameras and attachments that pre-date the 'crippled K-mount' which was introduced on late film cameras (removing the the stop-down coupling tab is what 'crippled' the mount, aperture then had to be set on the camera rather than lens). The Irix will therefore attach to any Pentax digital camera plus the later film cameras but not to the earlier film cameras and associated equipment such as the 1.7x AF adapter. So the Irix does attach to my digital cameras and film *ist but not to the film P30. And just for completeness, the Pentax 1.4 TC does not have a stop-down coupler tab so does attach to the Irix.

If I were bold and competent, I might try to remove the tab from the 1.7x AF adapter. But I am neither so the adapter remains unmolested and will never be attached to the Irix.

Steve

I've been through the same head-scratching exercise and did work out why it doesn't attach. Can't remember now, though, except that the Irix mount differs from the current K mount in a subtle way that doesn't matter with Pentax digital cameras or the Pentax 1.4x converter but does for this adapter from the F-series era. Thankfully, the Irix wasn't the only reason why I got the adapter .

The adapter also won't attach to the Laowa 25mm 2.5-5x macro, but I tried that just out of curiosity rather than thinking it might be even remotely useful!

Steve