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Forum: Pentax SLR Lens Discussion 11-13-2017, 08:40 AM  
DA 16-85 WR,show us what it can do.
Posted By Shedking
Replies: 732
Views: 97,899
I love how close you can shoot to the sun.
Forum: Pentax Q 11-13-2017, 08:34 AM  
IQ with adapted lenses?
Posted By Shedking
Replies: 23
Views: 2,039
I have been trying out several of my film-era lenses on my Q7 + Adapter Q for K Mount Lens in an attempt to rationalise some of my subjective preferences based on bokeh, colour, etc.

I put them all through their paces on MTF Mapper's lens grid target, trying to find their best aperture. In the case of the zooms, I was also trying to find their best focal length.

These results are comparative, using the performance of the 06 wide open @ 45mm as a benchmark, set arbitrarily to 100:

115: D-FA 100mm Macro, f/2.8 - f/4, performance falls off above f/5.6.

108: A135/2.8, f/5.6

103: A70-210/4 @ 70mm, f/6.3

97: M75-150/4 @ 75mm, f/6.3

77: M200/4, f/6.3

The conclusions:
  1. Primes are better than zooms.

  2. If you only have a zoom, stay away from the long end

  3. Most lenses are best about 1.5 stops off wide open

  4. Modern lenses are better than older ones

  5. The M series 200mm f/4 is a disappointment

  6. The D-FA 100mm macro is seriously, seriously sharp

As the focus throw of the 100mm macro is so short at longer distances, I'm wondering if I might use the focus clamp to turn it into a fixed focus lens at f/4. Has anyone tried that, I wonder? What would the hyperfocal be for a 100mm on a Q7, given the extra DOF that the crop factor gives?
Forum: Pentax Q 11-09-2017, 02:42 AM  
How to disable LCD auto turn off
Posted By Shedking
Replies: 7
Views: 494
I face exactly the same issue when attempting to manual focus a lens on the genuine Q/K adapter. By the time I've stopped down after focusing, the viewfinder has usually dimmed itself.
Forum: Pentax Q 11-06-2017, 11:43 AM  
How to disable LCD auto turn off
Posted By Shedking
Replies: 7
Views: 494
Set-up (Spanner) menu 2, Power Saving. Either clear the check box, or change the Auto Power Off setting.

You're gonna need a slack handful of batteries though...
Forum: Pentax Q 11-06-2017, 06:47 AM  
The "reach" of the Q - images
Posted By Shedking
Replies: 1,223
Views: 200,525
I have recently acquired an M75-150 / 4 for less than £9, an M200/4 for £23 and a Teleplus PZ-AF 1.4x teleconverter for £35, Compared to these, my £85 A135/2.8 seems expensive.

The three lenses went with me to the Lodmoor Nature Reserve in Weymouth, Dorset and took turns on the genuine adapter. The M75-150/4 seems very promising, even wide open at 150mm, as was the case for the picture of the coot. The Q7 struggled with the highlights, though.

The M200/4 was less successful. Granted, the redshank did wander off to leave only a corner crop with less-than-perfect focus, but the colours were rather muted. The surprise was the combination of the M200/4 and the Teleplus - better than the lens alone, even at ISO640. Judge for yourselves from the picture of the wading gull.

I've seen this before, and put it down to problems with stray light. The M200/4 has a rectangular rear baffle which, I assume, Pentax judged it needed to solve problems with....stray light. Fitting the teleconverter prevents the reflections. I shall clean the M200/4 and then recoat the inner surfaces with optical black.

The A135/2.8 seems almost made for this combination. Taken on another day, the Canada Geese dutifully sat very still...
Forum: Pentax Q 10-28-2017, 02:46 PM  
Let's share shots with Q!
Posted By Shedking
Replies: 5,703
Views: 778,542
"Flower Tree" by the Korean artist Jeong Hwa Cho, within an hour of sunrise. Q7 and 08 Wide Zoom:
Forum: Pentax Q 10-27-2017, 08:21 AM  
Let's share shots with Q!
Posted By Shedking
Replies: 5,703
Views: 778,542
Boy did I offend the gods when I suggested that many museums were over-lit. A couple of days later here I am making a pilgrimage to the Musée Lumière, Lyon, and the place is about as well-lit as the inside of my suitcase. Step forward Q7 and 01 prime...

The Lumière brothers once manufactured millions of photographic plates here including, as early as 1903, the very first "autochromes" . The factory was demolished in the late '60s to make way for an urban renewal project which never materialised.
Forum: Pentax Q 10-24-2017, 12:30 PM  
Let's share shots with Q!
Posted By Shedking
Replies: 5,703
Views: 778,542
There is a trend in European museums to allow photography without flash. The downside of this is that the curators feel that they have to over-illuminate the works, often with LED lights. In the case of paintings, shadows from the frames, plus WB issues, make for a tricky subject. Detail, rather than the full subject, has to be selected to avoid the worst of the shadows. Stained glass is easier to capture in its glory.

The Coronation of the Virgin by the Maestro Santa Clara de Palencia (late 15th Century) was largely in daylight. The image of St George and the Dragon (Grasset & Begule, 1889) was backlit. Q7 and 01 prime:
Forum: Pentax Q 10-22-2017, 02:37 PM  
Let's share shots with Q!
Posted By Shedking
Replies: 5,703
Views: 778,542
The perceived wisdom with Q lenses is to shoot wide open, or half a stop down from wide open.

Does that still hold true if you are subsequently going to rely on a shift lens effect to straighten things up? This lady's garland is sharper than her olive branch...surely there was enough DOF from the 01 prime?
Forum: Pentax Q 10-09-2017, 11:50 AM  
Let's share shots with Q!
Posted By Shedking
Replies: 5,703
Views: 778,542
Yes. The rear focusing group has to come out, as it is the main offender in this IF lens. I think there are similar threads here concerning problems with a milky blue cast when using third-party adapters. It seems to be the same type of problem.

FYI, my post #5624 was before painting. The Tokina's original internal finish is grey by comparison to Pentax. Two coats of blackboard paint make a genuine difference, to my eyes at least. If I were doing it again, I'd use a specialist astronomy black.
Forum: Pentax Q 10-08-2017, 03:36 PM  
Let's share shots with Q!
Posted By Shedking
Replies: 5,703
Views: 778,542
Here's a few lessons from earlier today:

Repainting the inner barrel of my Tokina 400mm SD AT-X should have been done when I first bought it. The improvement in contrast is noticeable.

I should have upgraded my tripod years ago. Carbon fibre is far better at absorbing vibration than aluminium.

You can never have enough batteries. The screen needs to stay on throughout as you go through the focus/stop down cycle, or the egret will wander out of the DOF...
Forum: Pentax Q 09-30-2017, 01:31 PM  
Let's share shots with Q!
Posted By Shedking
Replies: 5,703
Views: 778,542
An obliging heron stood stock-still and let me get this shot from nearly 100m away. Q7, Tokina 400mm SD AT-X at f/11 on genuine K/Q adapter.

Kitchen sink PP: fringe reduction, CA, contrast/black level, saturation, sharpness, etc., etc., but only cropped for portrait.
Forum: Lens Clubs 09-24-2017, 02:27 PM  
The 300mm plus lens Club discuss your long lenses.
Posted By Shedking
Replies: 27,045
Views: 2,306,608
Action from the Ferrari 70th anniversary event at Silverstone today. Nice spot on a slow corner, but I still need to shoot in JPEG to keep the frame rate up on the K-S2. I find the PLM has a quite different AF fine adjustment setting from my screwdrive lenses, which are mostly the same. Is that common?
Forum: Pentax Q 09-23-2017, 01:13 PM  
Let's share shots with Q!
Posted By Shedking
Replies: 5,703
Views: 778,542
This is a centre crop from the A135/2.8 on its own. I think that confirms prime + crop is the way to go:
Forum: Lens Clubs 09-17-2017, 07:38 AM  
The 300mm plus lens Club discuss your long lenses.
Posted By Shedking
Replies: 27,045
Views: 2,306,608
A series taken within 30 meters of each other, in the Arne Nature Reserve, Dorset. All are taken with my Tokina 400mm SD AT-X, at ranges from 2.5m to infinity:

East: Little Egret , West: Ringlet, South: Corfe Castle [I'm sure someone once asked to see more landscapes on this thread]....
Forum: Pentax Q 09-12-2017, 04:47 AM  
Let's share shots with Q!
Posted By Shedking
Replies: 5,703
Views: 778,542
The A-series 135mm/2.8 only has four elements in it, the same number as the Teleplus. Putting them together produces a FF equivalent of about 900mm on Q7.

I'm never going to be able to afford an FA* 600mm, so this is what I plan to use for extreme telephoto work, especially from the car window.

In good light, stopped down 2 stops, the result is well worth the modest outlay. CA, contrast, black level and saturation need to be looked at in PP.

There is some wind blur in this test shot, which makes it difficult to be sure, but I think the option of using the A135 alone and cropping might turn out to be sharper still.
Forum: Pentax Q 09-10-2017, 11:02 AM  
Let's share shots with Q!
Posted By Shedking
Replies: 5,703
Views: 778,542
A very territorial dragonfly on the Arne Nature Reserve gave me time to get my DSLR out of my backpack. This is the Q7 / 06 shot I took first (SOOP - Straight Out of Pocket). Head over to the 16-85 WR thread if you would like to see the KS-2 shot.
Forum: Pentax SLR Lens Discussion 09-09-2017, 07:47 AM  
DA 16-85 WR,show us what it can do.
Posted By Shedking
Replies: 732
Views: 97,899
There is a track on Coombe Heath, part of the Arne Nature Reserve in Dorset, where the territories of several dragonflies are routinely contested.
With a little patience, you can get very close, especially to the vanquished...
Forum: Pentax Q 09-04-2017, 12:04 PM  
Let's share shots with Q!
Posted By Shedking
Replies: 5,703
Views: 778,542
Site of a planned rail freight depot, Blisworth, Northamptonshire.

Q7, 08 lens, panorama stitched in Microsoft Image Composite Editor from three separate images.
Forum: Pentax Q 08-31-2017, 08:05 AM  
Let's share shots with Q!
Posted By Shedking
Replies: 5,703
Views: 778,542
Browsing the craft village at the Purbeck Valley Folk Festival...

Too much DOF, so tried Blur Control. JPEG OOC + Windows Photos "magic wand".
Forum: Lens Clubs 08-21-2017, 02:22 PM  
The Tammy Club!
Posted By Shedking
Replies: 2,684
Views: 427,241
Thank you! I'm not sure how much I had to do with it! This fly kept coming back to the same spot...
Forum: Pentax Q 08-18-2017, 02:35 AM  
Let's share shots with Q!
Posted By Shedking
Replies: 5,703
Views: 778,542
The coastline of the island used to extend much further out to sea, but it was quarried away for its limestone. The quarrymen left this pillar to show the original height of the sea cliff and the extent of the quarrying effort- call it vanity or pride, as you wish. This type of monument is known locally as a "knob".
Forum: Lens Clubs 08-13-2017, 03:20 PM  
The Tammy Club!
Posted By Shedking
Replies: 2,684
Views: 427,241
Farewell macro shot from my 90mm f/2.5 (Model 52B). Heading for a new life as an ultra-telephoto on Q....

Original handheld at 5000ASA. Denoised to 200ASA, then into Affinity Photo to remove residual grain (as Dust and Scratches).
Forum: Pentax Q 08-05-2017, 08:26 AM  
Let's share shots with Q!
Posted By Shedking
Replies: 5,703
Views: 778,542
Two interiors from the Priory Chapel at St. Michael's Mount, Marazion, Cornwall. Q7 and 01 Prime, available light.

My Q7 gives me the best results I have ever had photographing stained glass. The St. Aubyn family were collectors - this may be 15th Century.

The statue of St.Michael sparing Lucifer (before casting him into Hell) is modern, but the plinth is 4th Century.
Forum: Lens Clubs 08-04-2017, 10:24 AM  
The 300mm plus lens Club discuss your long lenses.
Posted By Shedking
Replies: 27,045
Views: 2,306,608
Mine was once declared Beyond Economic Repair. I think that technician might need retraining...

It's taken me a while to experiment with the right levels of fringe reduction (i.e. lots) and aberrations (not as much as you might think) in PP. The results on camera are not that impressive - perhaps due to the lack of in-camera correction.

The Tokina SD AT-X was marketed as Close Focus, and I find it is best from 2.5m to about 7m. It becomes more ordinary at infinity.

However, the real level up is Denoise. Before I remembered that I had it, I struggled to get anything sharp - even on a tripod, if the wind was blowing. Now, I can use anything from 2000ASA to 4500ASA on my K-S2 and get decent results.
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