01-27-2020, 09:05 PM
(01-26-2020, 06:21 PM)Brightcolours Wrote: Nuh, I am stating simple facts.You do not know the elements are the same. You have no way of knowing; and I will not take your word for it unless you somehow are an expert in optics. And even then I will be suspicious.
First, we do know the elements are the same. Pentax only decided to point out a 2nd kind of glass more than Tamron did. You can't just exchange one element of the same shape, in the same configuration, with glass that had different dispersion characteristics, and expect good results.
We also know that the coatings are the same. Just because Pentax decides to call their coatings "HD" means nothing, except maybe for Pentax fanboys. Canon, Nikon, Tamron, Sigma, Sony, Zeiss, Pentax update their coatings as the technology in the sector advances, and this Tamron lens uses... good Tamron coatings. The "SP" Pentax nonsense reads as follows:
"This lens features SP (Super Protect) Coating on its front surface. Applied by means of a PENTAX-exclusive fluorine deposition process, this coating is highly repellent to water, grease and dirt, making it easy to wipe off stains such as fingerprints. This frees the photographer from worries in outdoor photography.OTE:About KAF4 lens mount"
Exclusive... Right. Except that Nikon, Canon and others (including Tamron) also use such a fluorine coating for exactly the same purpose.
Lets read what Tamron writes about this Tamron lens:
"Fluorine Coating for protection and safe cleaning
The front surface of the lens element is coated with a protective fluorine compound that is water- and oil-repellant. The lens surface is easier to wipe clean and is less vulnerable to the damaging effects of dirt, dust, moisture and fingerprints."
Second, the lens is rebadged Tamron, built by Tamron just like the Canon and Nikon version are built by Tamron. There are physical differences, besides the cosmetic outer ones: the mount and electronics/firmware, between all 3 versions. Only the Canon and Nikon version, with VC, focus fast due to Canon and Nikon bodies, and the Pentax version will focus slower and more hesitant, so they felt the need to put the now VC-redundant button to use as a focus limiter.
Third, you are silly calling that a lie. The Tamron is a better lens. It renders.. better. It has... way less CA. It does not... shrink to 135mm at MFD like the Pentax does. The Tamron is objectively better.
Unfortunately, it's not easily to test this.
You do not know the coatings are the same; and name calling cannot substitute such knowledge. HD is designating a specific type of coating, so does SP - and they both work.
Fortunately, we might be able to test this. No, not you.
You can keep claiming it's a rebadge as much as you wish, you're still wrong. It's a customization. I already explained why.
You never tried the PLM lens, did you?
Last but not least, you are silly persisting on a lie.