Monday, June 27, 2011
Saturday, June 25, 2011
The User’s Review: Pentax ZX-7 35mm Film Camera
The User’s Review: Light-Field Camera: My Design, Prediction and Expectation
I read several articles on light field (LF) camera these days. It says that this kind of cameras will be available in market as soon as before the end of this year. Well, LF camera is new to me and most of the current camera users, but, as I learn from what I read, the mechanism of LF camera should be easy to understand and our current techs should have the ability to put it into a reality. On the other hand, the LF imaging is not new to certain animals such as insects since they have used this ‘tech’ for millions of years. The insects’ compound eyes compose of many light-field sensors. As one device, these sensors form a LF sensor array for imaging.
Let me explain the LF imaging in my own words. Suppose we have a square box and a point outside of the box. At the point we put a sensor or an eye to record the light coming from every point inside of the box. What we collect is the 3D light data from the box, which is called the light field (LF) in the box. When we display this data set on a 2D screen, the computer soft/hard-ware can regenerate two kind of images: 1) all-dot-clear (no-out-of-focus-dot) 2D image; and 2) assigned-point-clear (= focus point) image, which blurs out the dots off focus by computer calculation and is similar to the photo produced by our film and digital cameras.
Technically, there are two ways to design a LF sensor array: multiple micro-lenses assay and single-lens scanning array. The first kind has been developed, used and patented by INSECT, Inc. for a long time. The multiple micro-lenses assay focuses its different lenses at various points while the single-lens scanning array re-focuses its lens at different points during scanning. I am not sure who has the patent for this second type of array.
Again, the key issues in the LF imaging are the sensor array and the image-reproduction software. The assay is decisive in terms of image resolution and color-related features. The software helps us play the LF data to generate all-clear image, refocusing image or even 3D image.
It seems that I have to buy an all-new camera for LF imaging because I can’t imagine how to adapt my current cameras and lenses for LF usage.
Saturday, June 18, 2011
The User’s Review: Canon EOS 630, Released in 1989
The User’s Review: Canon Grips GR-10 L, GR-20 and GR-30 for EOS 600, 620, 630, 650 and RT
These grips work as both grip and battery camber cover on EOS 600, 620, 630, 650 and RT. Without a grip, the cameras will not power on.
Actually, GR-30 should be the standard model for those cameras. But what are the differences among the grip models? I am answering this question with the images and table.
GR-10, 20, and 30 |
Actually, GR-30 should be the standard model for those cameras. But what are the differences among the grip models? I am answering this question with the images and table.
Bottom views of GR-10, 20 and 30 |
GR-10 (L) | GR-20 | GR-30 | |
Grip | Large | Standard | Standard |
Bottom | Long | Standard | Standard |
Bottom strap eyelet | Yes | No | No |
Hand strap | Optional | No | No |
Shutter cable socket | No | Yes | No |
GR-20 and Remote Release 60 T3 |
Finally, I should mention that GR-20 and GR-30 are the same in dimensions, except the shutter cable socket on GR-20. I have a mid-size right hand, GR-10 feels a little bit bigger for my hand to hold.
Thursday, June 16, 2011
The User's Review: Tamron and Promaster Zoom Lens AF 70-300mm 1:4-5.6 LD Tele-Macro (1:2)
Although my Tamron and Promaster are with Pentax and Canon mounts, respectively, I see that they share more similarities in their specifications and appearances. Therefore, I put them together to review.
Marked specifications on both lenses besides those in this review's title: Macro (180-300mm); focus distance range of ∞-0.95 m (3.1 ft); filter size 62 mm; 6-digit SNs; Assessed in China. Both share the same lens hood and front cap.
On the Tamron, it's also labelled as 572D, Tamron, Japan. I saw Tamron 572D with Canon and Nikon mounts.
My Pentax mount Tamron (I believe, it's equivalent to Pentax F mount) also has a aperture ring, which makes it compatible with a wide range of Pentax SLRs from digital to MF bodies. With a AF Pentax body, the ring needs to be lucked at A mark. The actual focus range on a Pentax DSLR should be between 112-480mm due to the 1.6x factor. Both Tamron lenses operate smoothly, I mean the zoom and focus rings. Comparing with my Simga 70-300mm 1:4-5.6 (Macro 200-300) (with a Minolta A mount), its zoom ring feels harder to turn between 150-300 mm, which is not happened in my two Tamrons.
I like Tamrons because they produce good images at their long end and in dim conditions. Probably Tamrons have a larger front element of 62mm (vs. 58mm in my Sigma).
In the two above images shot with my Tamron for pantax, the long hairs around the squirrel's mouth and bright lines on the moon were not caught by my bare eyes from the distances on site. I mean that the images through the lens picked up more details than my eyes.
Marked specifications on both lenses besides those in this review's title: Macro (180-300mm); focus distance range of ∞-0.95 m (3.1 ft); filter size 62 mm; 6-digit SNs; Assessed in China. Both share the same lens hood and front cap.
On the Tamron, it's also labelled as 572D, Tamron, Japan. I saw Tamron 572D with Canon and Nikon mounts.
My Pentax mount Tamron (I believe, it's equivalent to Pentax F mount) also has a aperture ring, which makes it compatible with a wide range of Pentax SLRs from digital to MF bodies. With a AF Pentax body, the ring needs to be lucked at A mark. The actual focus range on a Pentax DSLR should be between 112-480mm due to the 1.6x factor. Both Tamron lenses operate smoothly, I mean the zoom and focus rings. Comparing with my Simga 70-300mm 1:4-5.6 (Macro 200-300) (with a Minolta A mount), its zoom ring feels harder to turn between 150-300 mm, which is not happened in my two Tamrons.
In the two above images shot with my Tamron for pantax, the long hairs around the squirrel's mouth and bright lines on the moon were not caught by my bare eyes from the distances on site. I mean that the images through the lens picked up more details than my eyes.
Tuesday, June 14, 2011
The User’s Review: Canon EOS 55 SLR Camera, Release in 1995
Technically, Canon EOS 55 is one of the AF cameras that I like most because of the three reasons: 'eye control' of AF and DOF, panorama format and many associates (remote, grip, D-size battery pack...) from Canon. The DOF eye control makes 55 and its siblings, Elan IIe and 50e, to be different from all other AF SLRs and DSLRs.
In North America, EOS 55 is rare in the second-hand market and has never existed in the new item market because of EOS 55's ‘JDM’ status. If you have no idea about ‘JDM’, google it.
In North America, EOS 55 is rare in the second-hand market and has never existed in the new item market because of EOS 55's ‘JDM’ status. If you have no idea about ‘JDM’, google it.
There are two color versions of EOS 55: all back and black/silver. In mid June of 2011, a black/silver was listed for USD 50 including shipping with ‘Buy It Now’ on ebay, I bid my black vision at USD x (Wu Shi Si dian WU WU) plus 8.5 shipping on June 4. Added second black body (at si shi + 8.5) to my collection on March 13, 2013.
In USA, we see a lot of Canon Elan II and IIe, optionally with date back. Their prices range between USD 15 – 40. Generally, EOS 55 is identical to its sibling model, IIe, except in only black/silver color and no panorama function.
Viewfinder of Canon EOS 55. The four orange-color arrows indicate that the panorama is in action. |
In terms of ‘Eye Control’ function, EOS 55 is unprecedented and, so far, unrepeated in all SLR and DSLR cameras. It has both eye-picked focus point (one out of three) and eye-controlled DOF (the upper-left diamond sign) in its viewfinder. Although the later Canon EOS models, Elan 7e and 7ne, inherit the eye-picked focus point (among 7 points), but loss the eye-controlled DOF.
EOS 55 left vs. Elan IIe right |
Once the panorama switch is on, two panels block the upper and lower portions of the film window behind the shutter. More interestingly, there are no panels to cover the correspondent areas in the viewfinder, as seen in Minolta STsi and XTsi. In EOS 55, instead, there are two horizontal lines marked the panorama area on the focus screen, four orange-color arrows on both sides of the lines will light up by half-way press of the shutter release and indicate the panorama format.
The two images above are of my chrome/black EOS 55. In Jan. 18 of 2012, I won it at USD 8.5 with 14 shipping on ebay. The chrome parts are made of aluminium instead of brass.Therefore, this body will never be brassing, but may be aluminiuming with aging?
Saturday, June 11, 2011
The User’s Review: Canon EOS Rebel X and XS (EOS 500), both released in 1993
Both in light weight, the compact Rebel X and XS cameras are different by the two lights, flash and AF-assistant lights on XS only. Therefore, there is one extra button besides the self timer on SX to control the flash.
It said that S in the model code represents flash. Maybe should include the AF light also.
It said that S in the model code represents flash. Maybe should include the AF light also.
EOS 500 marketed in other parts of the world is another name of X s. |
The User’s Review: Nikon N2020 (F-501 outside N. America), A piece of history in Nikon AF
Looking identical to Nikon N2000/F301 (released in 1985), Nikon N2020, released in 1986, is revolutionarily different from all previous Nikons by an AF driving motor installed in the body, which has a CCD ‘eye’ for AF through TTL "passive" phase-detection. This AF approach is more precise than the commonly-used active method.
With automatic film loading and advance, N2020 can shoot as faster as 2.5 FPS. However, the user has to use your hands to rewind the film and to set the film speed. With a conventional wheel of film speed, film speed can be set automatically (turn the wheel to the DX mark under the window) if there is a DX CAS code on your film cartridge, or set manually by turning the ISO wheel to match the speed number.
N2020, well built, is in black color with a horizontal RED line in the grip. N2020 is powered by four AAA batteries installed on a rack or four AA batteries directly installed in the battery bottom chamber with an optional bottom cover. N2020 feels more solid than the later models such as N4004, N4004s and N5005 although the AF in them, especially in N5005, is faster.
Visit my review on the Multi Bata Back MF-19 if you are interested.
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