HM6 vs HM7 - Zoom files not being created or used?

Please post all questions and comments regarding Help & Manual 7 here.

Moderators: Alexander Halser, Tim Green

Post Reply
Mike Law
Posts: 9
Joined: Wed Feb 04, 2015 11:30 pm

HM6 vs HM7 - Zoom files not being created or used?

Unread post by Mike Law »

After upgrading to HM7, I noticed that my file sizes were different when I publish to web help.

Digging a bit deeper I noticed that HM6 and HM7 file sizes in the output folders were different due to the zoom images not being created by HM7. To test, I opened the same hmz file in HM6 and HM7. I published it to two different folders and compared.

The HM6 output folder creates the zoom images (my images are about 35% zoom of original) while the HM7 folders doesn't create the zoom and only uses the original images (see the attached screenshot).

Is there a setting in HM7 that can mimick the original behaviour of HM6? Since I also make a version for mobile use, having large MB files is a no-no.
You do not have the required permissions to view the files attached to this post.
User avatar
Tim Green
Site Admin
Posts: 23156
Joined: Mon Jun 24, 2002 9:11 am
Location: Bruehl, Germany
Contact:

Re: HM6 vs HM7 - Zoom files not being created or used?

Unread post by Tim Green »

Hi Mike,

This has been changed with the support for responsive images and cannot currently be turned off. In the long run you will also need it for mobile sites because the screens of mobile devices are all moving towards insane resolutions, most of them much higher than computer monitors. Sony has actually just released a phone with a 4K screen. :)
Regards,
Tim (EC Software Documentation & User Support)

Private support:
Please do not email or PM me with private support requests -- post to the forum directly.
User avatar
Martin Wynne
Posts: 2656
Joined: Mon May 12, 2003 3:21 pm
Location: West of the Severn, UK

Re: HM6 vs HM7 - Zoom files not being created or used?

Unread post by Martin Wynne »

Hi Mike,

If the PNG files are screenshots or diagrams, you can reduce the file size significantly by reducing the colour-depth to 8-bit (256-colour). Gradient fills will become steppy, but otherwise for screenshots you will hardly notice the difference. Even for some photos it is barely noticeable.

regards,

Martin.
Simon Dismore
Posts: 454
Joined: Thu Nov 16, 2006 1:29 pm
Location: London, UK

Re: HM6 vs HM7 - Zoom files not being created or used?

Unread post by Simon Dismore »

I've tried a few tests with a 1920x920 screenshot of a Google maps earth view with photographs underneath, i.e. lots of continuous tone not ideal for png compression.

The original PNG-24 file = 3063KB.
When exported as PNG-8 without dither from Photoshop = 952KB, but tonal gradations become really ugly.
When exported as PNG-8 with diffusion dither from Photoshop = 1083KB, and tonal gradations were OK-ish (slightly "orange-peel" in places).

I then tried processing with voormedia's TinyPNG smart lossy compression. The original 3063KB file was reduced to 1059KB with better tonal gradations than PNG-8 in my opinion, so that's a possible alternative.

However, my roughly 3:1 difference in file size is nowhere near what Mike is getting from the HM6 zoom method. His folder screenshots show 2886KB at full size reducing to 99KB and 1971KB to 52KB at 35% zoom.

If Mike is the author of the PDF Maps Help I'd be interested to hear his perspective on high-resolution phones etc.
Mike Law
Posts: 9
Joined: Wed Feb 04, 2015 11:30 pm

Re: HM6 vs HM7 - Zoom files not being created or used?

Unread post by Mike Law »

Simon Dismore wrote:I've tried a few tests with a 1920x920 screenshot of a Google maps earth view with photographs underneath, i.e. lots of continuous tone not ideal for png compression.

The original PNG-24 file = 3063KB.
When exported as PNG-8 without dither from Photoshop = 952KB, but tonal gradations become really ugly.
When exported as PNG-8 with diffusion dither from Photoshop = 1083KB, and tonal gradations were OK-ish (slightly "orange-peel" in places).

I then tried processing with voormedia's TinyPNG smart lossy compression. The original 3063KB file was reduced to 1059KB with better tonal gradations than PNG-8 in my opinion, so that's a possible alternative.

However, my roughly 3:1 difference in file size is nowhere near what Mike is getting from the HM6 zoom method. His folder screenshots show 2886KB at full size reducing to 99KB and 1971KB to 52KB at 35% zoom.

If Mike is the author of the PDF Maps Help I'd be interested to hear his perspective on high-resolution phones etc.
Thanks Tim and to all of the repliers. Totally understand the movement towards ultra high resolution screens.

For now I'm keeping the same resolution but using Fireworks CS6 to optimize.
Original PNG24 file = 2886 KB
After Fireworks CS6 saving to PNG24 = 334 KB
After Fireworks CS6 saving to PNG8 = 94 KB

Quality suffers at PNG8, so I will most likely stick to PNG24 optimized by Fireworks. But file sizes are still not close to behing sub-100 KB (which is great on mobile, no matter what device or network). Also, it's another step to optimize PNGs but at least the batch process in Fireworks does it quickly.

Simon: yes, I work on PDF Maps Help and other Avenza Help and documentation. We always cater to the lowest device still supported by our app and unfortunately it's still an iPhone 4. When we drop support of it, we can definitely move towards having higher resolution images. This is our first iteration of the help and we have had a lot of positive feedback with it.
Post Reply