Hi there, the information provided in the previous post only relates to the handling / creation of the images to be used in your slider. You can but are not forced to create a new media type.

Reasons for:

1. Potentially makes it clearer for your editors - because one of the features of umbraco's image picker is to choose a particular folder of images, you may decide to create two media types a) one called slide image folder b) one called slide image. When you set up the image picker it would point to the slide image folder, which only contains slide images ( this is because you will have configured using the 'structure' tab on the media type to only contain slide images)
2. You already have a website which uses an existing 'image' media type but that media type does not currently use image cropper. Making changes to the image media type in this case would probably involve altering page templates so that images can continue to render on your site
3. It just doesn't make sense in your own mind that every image on your site would have crop sizes attached to it which only ever relate to the image slider

Reasons against

1. Extra effort. For it to make sense you would need to create the two media types, the first as your folder and the the one for your image
2. In 7.2 I experienced a problem where if you were editing a slide and you uploaded a new 'slide image' (your new media type), instead creating a slide image once upload was complete umbraco created a new 'image'. To get round this I created a new application event handler and used the MediaService.Saved event to change the media type to my slide image.

Aside for the image editing side of things it would be difficult for me to prescribe the approach you should take for managing the slider itself as every situation is so different. Here are some suggestions

Using the umbraco 7 grid? If yes look at leblender this video https://www.youtube.com/watch?v=ChGZ_CDnNls demonstrates creating an image carousel. I would generate a list of images which you would then wire up to slick image when displaying on the front end.

Only ever going to display images i.e no title or description overlays? If you are not using the grid but the slider will only ever display images then you might decide to create a single datatype which you call slide image picker

When you select what type it is you would choose image picker and choose the slide image folder detailed earlier as your image source.

Tick the box allowing multiple selections.

Create one new document type called slider and add a property which you might call images, in the 'type' drop down you would select your slide image picker.

Hi

I have two custom media types (image and folder)

So I should be able to do this OK?

    private WidgetViewModel GetContent(IPublishedContent content)
    {            

        var widget = new WidgetViewModel
        {
            Id = content.Id,
            Title = content.Name,
            Url = content.Url,                
            BigImageSrc = content.GetCropUrl("umbracoFile", "details")
    };

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